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12.14pm
Council urges those in Rolleston or Tai Tapu to reduce all water use. Currently Tai Tapu sewerage is going into the Halswell River due to the city's network failure and Rolleston's sewerage is overloading the small treatment site that is still operating. A welfare centre is now open at the Rolleston Community Centre on Rolleston Drive.
11.57am
The Ministry of Education has confirmed that three schools will be closed tomorrow - Kaiapoi Borough School, West Melton School and Hillmorton High. The Ministry is working with principals and boards to determine the extent of any damage to other schools.
11.55am
It may be two to three days before power can be restored to some houses. Inextreme cases, where a single home or business is still without power in an area where power has otherwise been restored, it may up to five days. Orion is currently focusing on Avonside, Brighton and Halswell, as well as rural areas around Highfield, Greendale and Brookside.
11.53am
The council's Building Evaluation Team is moving through the cordoned off area of the central city, inspecting all buildings within this zone.
Each building will be tagged after it has been inspected with red placards assigned where buildings are considered unsafe and can not be entered; yellow placards assigned where restricted use is permitted; and green placards assigned where there are no restrictions on a building's use.
It is hoped that this process can be completed for all buildings within the cordoned off area by the end of today. Once this information is available, yellow and green placarded buildings will be able to be cleaned up on Monday.
There will be no public access to the cordoned central city area before Monday with the exception of residents. The cordon covers the area bounded by Madras, St Asaph, Montreal and Kilmore Streets.
11.44am
Overnight hospital activity has been reported as 'quiet'. Ambulance services have returned to normal operational levels and all hospitals are functioning fully, despite 'minor infrastructure issues'.
11.33am
Christchurch currently has a relatively high rate of H1N1 swine flu virus, which health officials believe could swell as accommodation is disrupted.
The increased risk is being addressed by the Public Health Unit and District Health Board. There are ample reserves of antivirals available in the area.
11.29am
KiwiRail has transported 14 milk tankers of water - each containing 20,000 litres - from Temuka to Ashburton by rail. The water train was parked in Ashburton overnight as the line to Christchurch was closed. It has reopened with speed restrictions.
11.03am
There is a shortage of drinkable water in Waimakariri, mostly Kaiapoi. The Selwyn District has nearly returned to normal in urban centres but rural areas remain problematic. Rolleston's water is contaminated.
Residents of Canterbury still advised to boil water prior to use, also to avoid recreational use of water as rivers have been affected with sewage.
10.54am
Christchurch City Council, Waimakariri District Council and Selwyn District Council currently still assessing damage in their own areas.
The Earthquake Commission has so far received approximately 2800 claims for damage to homes.
10.40am
Hundreds of payphones in Christchurch are now free for local, national and mobile calls. Telecom says power outages and other damage has meant parts of the city are still without landlines.
A decision is expected soon on whether schools in the region will open tomorrow.
10.13am
Mayor Bob Parker says no decision has been reached on whether inner city Christchurch business will be permitted to open tomorrow, as experts assess safety risks in the area.
10.03am
Magnitude 4.1 aftershock hits 20km south-west of Christchurch. At least 47 aftershocks have been recorded over the weekend.
9.46am
4.5 aftershock 20km west of Christchurch, 8km deep.
9.37am
GNS seismologist John Ristau says structures weakened by the main earthquake could be brought down by the aftershocks which continue to affect Christchurch.
"It can be difficult to find all the active faults" Ristau told Newstalk ZB after it was revealed that a "hidden" faultline was the cause of yesterday's earthquake.
Ristau expects the aftershocks to die off as the week goes on.
9.30am
Christchurch City Council says 50 extra search and rescue personnel will assist in the city.
Lines company Orion says some people in the region may not receive power until the end of the week.
8.55am
Weather analyst Richard Green has told Newstalk ZB the Canterbury region is set to face norwesterly winds between 60 and 130 kilometres an hour.
Winds of up to 80 km/h have been measured near the epicentre of the earthquake in Darfield.
8.43am
Aftershocks continued to rattle Christchurch overnight, with locals reporting tremors approximately every 30 minutes.
The Christchurch council said public access to the central city would remain restricted to residents only. People in the area have been advised to minimise their travel.
The council said it hoped to complete building assessments within the central city zone today.
The water supply is back on for at least 85 percent of the city's residents, however issues with the supply may still force evacuations in Avonside, New Brighton and Brooklands.
8.13am
4.1 aftershock closer to Christchurch (20km south-west of the city), at a depth of 20kms.
8.00am
More aftershocks - 4.2 at 7.41 (south east of Darfield); 4.2 at at 7.51 (20km west of the town).
7.30am
3.7 magnitude quakes near Darfield at 7.11 and 7.31, 15km and 5km deep respectively.
5.53am
4.5 aftershock 20 km south of Darfield, 15km deep.
5.30am
Large 4.6 magnitude aftershock hits 20km south of Darfield at 5.17am, at 5km depth. Three minutes later is followed by 5.1 magnitude, 10km south of the town, depth 9kms
4.31am
3.8 aftershock 20km east of Darfield,7km depth.
4.23am
4.4 quake hits 10km south-west of Darfield at depth of 5km
4.20am
3.9 magnitude aftershock 30km south-east of Darfield hit at 2.42am (5km depth); 4.0 aftershock at 4.08am, same area but 15km deep.
2.35am
3.4 magnitude aftershock hits 10km east of Darfield at a depth of 7km.
1.58am
3.2 aftershock 10km east of Darfield at a depth of 6km.
12.57am
3.8 aftershock hits 'within 5km of Darfield' according to Geonet. Depth 8km.
Sunday 12.10am
3.8 aftershock hits 20km south-east of Darfield at a depth of 6km.
21.10pm
Some scientists are investigating whether the 7.1 magnitude earthquake which struck Christchurch and its surrounding communities today was actually two or three shocks in quick succession.
The US Geological Survey (USGS) in Golden, Colorado, has said that scientists are still trying to reconstruct the way today's quake played out.
"We think that this is a very complex event," said geophysicist Paul Caruso. "We think that the main shock may have consisted actually of three earthquakes."
GNS Science in Wellington - which changed its initial calculations of a 7.4 magnitude shake 30km west of Christchurch to a 7.1 shake 40 km west - said it could not confirm the mechanisms of the earthquake.
20.05pm
Severe winds predicted across Canterbury could see more building collapses following today's powerful earthquake, says WeatherWatch.co.nz.
With numerous buildings badly damaged, strong gusts could see more brick walls and roofs come down, according to analyst Philip Duncan.
"People should spend Sunday preparing for more possible powercuts. Stock up on batteries and ensure you have torches."
19.30pm
Power has now been restored to 90 per cent of urban Christchurch and 80 per cent of the rural network.
Meanwhile, crews are working to restore rail links to Christchurch from the south so supplies can be delivered.
KiwiRail chief executive Jim Quinn told One News there were plans to bring in almost 300,000 litres of drinking water from Temuka later tonight.
19.00pm
Gas is once again safe to use, local supplier Contact Energy says.
However, people should check the gas lines to their house, ensure that gas bottles are standing upright and hobs are in working order.
18.45pm
All Selwyn residents are being asked to conserve water, particularly those in Rolleston, as the Rolleston water supply is contaminated.
Christchurch City Council has warned retailers and building owners with concerns about the structural integrity of their buildings not to enter them.
18.10pm
Prime Minister John Key says it is a "miracle" that nobody died in today's earthquake.
He told One News the cost of the damage was likely to be in the billions.
18.05pm
One of New Zealand's oldest schools, Christ's College, has suffered earthquake damage.
Spokeswoman Jane Leese says there is minor damage to some of the older buildings and some chimneys have fallen off onto the dining hall below.
18.00pm
ANZ has announced a $1 million donation to support Canterbury residents and businesses in the aftermath of today's earthquake.
Acting chief executive Steven Fyfe said in addition to the $1 million donation to the proposed Mayoral Relief Fund, the ANZ and National Banks will also offer a special package of assistance for personal and business customers impacted by the earthquake.
An appeal account for people to donate to the proposed relief fund will be set up once details of the fund are finalised by the Christchurch City Council.
As part of the package of support for affected customers, ANZ and the National Bank will:
- suspend repayments on all loans for three months
- waive fees associated with restructuring business loans considered necessary due to earthquake impacts
- waive early withdrawal costs for term deposits
- consider temporary adjustments to customer lending limits including credit cards
17.50pm
Cantabrians are being urged not to drive unless absolutely necessary as officials try to gauge the damage caused to roads in this morning's earthquake.
Initial inspections showed the region's highways appeared to have held up well, but it could be several weeks before the full extent of any damage was known, NZTA spokesman Peter Connors said.
State Highway 77 between Methven and Windwhistle is the only state highway currently closed due to earthquake damage.
17.40pm
A Royal New Zealand Air Force C-130 Hercules is currently enroute to Christchurch carrying 42 search and rescue (USAR) personnel and three dogs.
Two Iroquois helicopters from No. 3 Squadron at Ohakea have also been tasked to assist in Christchurch.
They will be available to undertake aerial reconnaissance and damage assessment as required by Civil Defence.
17.35pm
The largest aftershock yet has been felt in Canterbury.
The 5.4 magnitude jolt was centred 10 km southwest of Darfield at a depth of 10 km.
17.25pm
Fonterra says it has four tankers loaded with water at Clandeboye ready to go if required.
Although its Plains site had sustained some superficial damage and some farmers without power were unable to milk, it did not expect any impact on production.
17.20
Telecom says its services are working well in the South Island following today's earthquake.
It says its 111 services are fully available and fixed line infrastructure is performing well, as are both Telecom mobile networks.
17.08pm
The Salvation Army has launched an appeal to help feed and support those affected by today's quake.
"People will be in shock, some have lost possessions and housing, and many will need food and comfort," Salvation Army national fundraising coordinator Major Robbie Ross said.
The Salvation Army fed about 1000 people at two Christchurch locations early this morning, he said.
Civil Defence urged people in the greater Christchurch area to ensure they had plans before nightfall.
"If your chimney is damaged and/or you feel unsafe in your home, can you camp at a neighbour's or a relation's for the night?" Civil Defence duty manager John Talbot said.
"It's important people make a plan before it gets dark."
17.05pm
Power has been restored to 77 per cent of Christchurch city and is still expected to be restored to 90 per cent or more by tonight.
Rural areas in central Canterbury are largely out of power as a result of downed poles or lines.
Wigram airport is not currently operating.
17.00pm
Welfare centres for those who need shelter have been opened at Linwood High School, Burnside Welfare Centre and Addington Raceway Centre.
Canterbury police will be supported by 80 officers flying in from Auckland this evening to assist with general duties and recovery.
There is a formal curfew in the CBD between 7pm and 7am.
It is likely the army will be called in to assist with the cleanup.
16.32pm
BJ's Massage Parlour in the CBD, on the corner of Worcester and Manchester Streets, burst into flames this afternoon but has been brought under control.
The fire is believed to have been caused by a surge as gas and power supply was turned back on.
Newstalk ZB reporter Lesley Murdoch is at the scene and says smoke is pouring out of the building.
16.02pm
Residents in Christchurch's central district are to be evacuated this afternoon due to the risk from falling masonry, according to Radio New Zealand.
Search and rescue dogs are also being used following reports of people trapped under rubble but so far have not located anyone.
15.55
Radio New Zealand reports that the historic Empire Hotel on London St in Lyttelton was badly hit by the quake and is considered very unstable.
District chief fire officer Mark Buckley said the hotel's facade, thought to weigh 20 tonnes, was hanging by a thread.
15.42pm
Today's 7.1 magnitude quake west of Christchurch may have occurred on a "new" fault line.
Geologists have not yet been able to link it to a known fault; in the past few years, researchers have found that Canterbury is riddled with more earthquake-generating fault zones than previously thought - some as close as 20km to central Christchurch.
Canterbury University scientists have said there are about 100 fault lines and fault segments around the region, rather than the half-dozen active faults that were known about 20 years ago.
The closest known faults to Christchurch capable of generating powerful quakes are in the Rangiora-Cust area, near Hororata, and near Darfield.
15.40pm
AMI Stadium has suffered only minor damage, Rugby NZ 2011 chief executive Martin Snedden says.
"The very preliminary assessment is that there's no structural damage there, that there's a heap of minor breakages and what not, but no structural damage," Mr Snedden told NZPA.
Mr Snedden said the quake had come just days after Rugby NZ 2011 had looked specifically at how such a situation would be handled if it were to arise during the tournament.
15.35pm
Power is now back on to around 70 per cent of Christchurch.
However, residents are being warned to be extremely careful around low lying power lines in the aftermath of this morning's earthquake.
Orion chief executive Roger Sutton says people must treat them as live and stay away from them at all times.
Tremors are still occurring regularly, many of which have registered over four or five on the Richter scale.
15.22pm
Two Red Cross emergency management teams comprised of 21 people are in action in Canterbury.
Four emergency staff and volunteers trained in light rescue, casualty handling, first aid and welfare are using 4WD vehicles to look for people cut off in the countryside west of Christchurch, near the epicentre of the earthquake.
Two members of the Red Cross Wanganui Response Team have also been deployed to Christchurch and more volunteers from Nelson and Blenheim are on standby.
A portable repeater station has been established on the Port Hills to provide VHF communications as electricity and landlines are not dependable.
14.55pm
Police say Christchurch CBD will be closed until tomorrow while assessment of damaged buildings is carried out.
No businesses or licensed premises will be open and only innercity residents will be allowed in.
Police will man cordons throughout the night.
The area affected is contained within the Montreal Street, Kilmore Street, Madras Street and St Asaph Street area.
A state of emergency in Christchurch city, Selwyn and Waimakariri Districts is likely to be in place until noon Monday, according to Environment Canterbury.
14.50pm
The University of Canterbury and Lincoln University are currently closed while their campuses are assessed for health and safety issues, and will not reopen until Monday September 13.
In a statement, the University of Canterbury said confirmation of its re-opening would be made no later than 5pm on Wednesday September 8. All students, including post-graduate students should stay off campus.
However, there will be no change to the final exam timetable.
Check the university website for information and updates.
14.45pm
Christchurch's after hours surgeries are reporting a steady numbers of patients but say they are coping well.
Hillmorton and The Princess Margaret Hospitals have been told that the main power supply will be running again in the next few hours.
Both the Lincoln Maternity Hospital and Burwood Birthing Unit will be closed until further notice.
Women who were intending to birth at either should go to Christchurch Women's Hospital. Women affected by the changes are being contacted along with lead maternity carers and staff at the closed units.
Christchurch Hospital is fully staffed and functioning well. District Health Board communications manager Michele Hider said the number of cardiology admissions had been higher than normal.
A neurosurgeon told Radio New Zealand most patients' injuries were minor, including lacerations and minor head trauma.
14.22pm
Power is being restored to Christchurch area by area.
The network was not badly damaged but power was cut as a precaution.
Electricity should be returned to about 90 per cent of Christchurch by the end of the day.
14.20pm
Cellular networks in Canterbury are being restored to normal with both generator and mains power, but users are still being urged to stay off their cellphones unless they need to make essential calls.
The earthquake led to widespread power cuts across the region this morning, and cellular networks began to run out of power as batteries went flat soon after.
Both Telecom and Vodafone said although the networks did not crash, they immediately encouraged people to stay off their cellphones.
Some cellular calls were affected but both major cellphone companies said the networks generally performed well.
Vodafone's Paul Brislen said the company had asked TVNZ to stop asking people to send in footage of the quake damage on their cellular phones because it was threatening to overload the network.
Robin Kelly, a spokesman for network maintenance company Chorus, said the fixed line network had remained stable.
14.10pm
Waimakariri District Council is advising Kaiapoi residents to leave town if possible, as it may be a long time before water or sewerage services are restored.
On Radio New Zealand, council chief executive Jim Palmer said the council was setting up an emergency centre.
Local MP Kate Wilkinson said the streets had been cordoned off and community patrols were working to keep people out of danger areas.
Kaiapoi's main road is closed, as is the bridge in the middle of the town.
13.55pm
Christchurch Airport is once again operational as of 1.30pm. Travellers should contact their airline prior to travel to check flight schedules.
After the airport runways and infrastructure were assessed for damage, the airport reopened before the Prime Minister and other ministers were due to arrive.
Air New Zealand said 77 domestic flights and 11 international flights had been affected by the airport closure, and it was likely to take the rest of the day to clear the backlog of passengers.
Inbound international flights had been diverted to Auckland and Wellington airports.
13.50pm
MetService has issued a severe gale warning for the city, predicting winds averaging 65kmh (gale force) with gusts to 130km.
The 7.1 magnitude quake has left many homes exposed to the elements, which are expected to take a turn for the worse with gales forecast for tomorrow afternoon.
WeatherWatch.co.nz said strong winds would increase during the day, with severe gales gusting to 130kmh possible later in the day.
13.19pm
Dozens are gathered on the grass bank areas outside Christchurch Airport with luggage. Police are preventing people from entering the grounds.
13.10pm
Canterbury electricity supplier Orion is confident that 90% of Christchurch city will have power restored by nightfall, says spokesman Roger Sutton.
He says rural areas will take longer, but the company is currently assessing how much damage has been done outside main centres.
He advises those whose houses have been damaged to turn power off at the mains.
12.56pm
NZTA Canterbury state highways operations manager Peter Connors said SH77 between Methven and Windwhistle and Mid Canterbury had been closed. SH75 Taipapu to Kaituna in the Banks Peninsula area near Christchurch had also been affected but remanded open.
Bridges on SH1 over the Ashburton and Rakaia Rivers and across the Waimakariri River north of Christchurch are operational. The Chaney's Road on ramp on to SH1 north of Christchurch is closed.
12.53pm
The cost of damage from today's devastating quake could be as much as $2 billion, Earthquake Commission chief executive Ian Simpson says.
"It's very early to start estimating the numbers so far," he said. "At a guess, and it is just a guess so far, we are looking at ...around 100,000 claims in total from the event and the cost will be easily into the hundreds of millions of dollars just for EQC for the residential property... It could reach between one and two billion dollars."
People who had private house insurance were automatically qualified for EQC cover.
12.49pm
One man in his 50s remains in a 'serious condition' after being struck by a falling chimney.
12.42pm
Estimates that power could be restored to 90 per cent of Christchurch by 6pm tonight.
12.39pm
Canterbury Federated Farmers said that of growing concern to farmers was a MetService weather warning that had been issued for Sunday evening - especially since power may not be restored to rural areas for up to two days.
12.31pm
Civil Defence Minister John Carter says evacuation of "a significant number" of Christchurch city residents will begin shortly.
12.23pm
The Army is preparing to send troops to assist in Christchurch if required.
12.16pm
The Department of Corrections says there has been no structural damage to the area's prisons. They are currently running on back-up power and there is no water supply.
12.06pm
Christchurch airport staff spent the morning turning people away, with the control tower and terminal reportedly suffering damage.
11.55am
Prime Minister John Key says we "will not let Christchurch suffer this great tragedy on its own".
Mr Key is currently leaving on a Air Force plane from Whenuapai to Christchurch to survey the damage after this morning's 7.1 magnitude earthquake.
He said initial estimates of the damage meant the bill could be substantial.
11.45am
Experts say damage in Christchurch is in pockets, especially in areas where water-logged soil ruptured water and sewerage lines.
11.30am
The army is on standby is ready to mobilise, if needed, says Civil Defence Minister John Carter.
11.02am
The AA reports that Lyttleton tunnel reopened after safety checks. AA says SH74 ring road around Christchurch closed at Bromley due to road problems.
10.53am
Civil Defence Minister John Carter says New Zealand has been "extremely lucky" to have escaped without any deaths in the Christchurch earthquake, which struck Canterbury at 4.30am today.
He said Christchurch had been rocked by both the earthquake and a series of rolling aftershocks.
But he said the people of Canterbury should be reassured that Government and Civil Defence were working hard to ensure the city is safe.
10.30am
Fears for the state of Kaiapoi, near Christchurch are growing.
Reports are emerging of significant damage to the main street, cars damaged and buildings cracked.
10.20am
Herald reader, Anne Kenyon, sent us this report from Christchurch after this morning's 7.4 magnitude earthquake.
"We are extremely lucky to have escaped damage and or injury. In all of my 56 yrs, it has got to be the scariest thing I have ever experienced. I didn't know quite what was happening as I awoke to violet shaking and noise that I can best described as like a freight train going through our bedroom, my first thought was of my daughters, and my Grandchildren. It has taken a few hours for me to feel settled again, I am thankful that we are all safe and well."
10.16am
A state of emergency has just been declared for all of earthquake-stricken Christchurch.
Civil Defence Minister John Carter said the United Nations had contacted the Government and was being kept informed of the situation.
Plans were in place to get milk tankers full of water into the city but the water was likely to be rationed, he said.
Mr Carter said many people were suffering from shock but he urged the public not to flood the hospital with minor injuries. They should instead go to their local 24-hour medical centres.
10.08am
Herald reader, Kelsey McIntyre, sent us this account of feeling the earthquake as far away as Taranaki.
"I live 13km East of Inglewood, Taranaki, and felt the Christchurch Earthquake this morning. Not totally sure of the time but was strong enough to wake me up, and I could hear the pictures on the wall in the hallway lightly bouncing off the walls and the also the door swinging back and forth."
10.05am
Darfield Primary School principal Markham McMullen said this morning's earthquake was like facing a train.
"It just kept coming, it went and on and on."
The force of the initial quake, about 4.35am, threw him and his wife, Annita, out of bed, he said.
"It was absolutely terrifying. We grabbed our daughter, Sophie, from her room and crouched under a doorway. The TV was flying around the room and the reality kicked in. It was very scary.
"Our china cabinet has crashed, pictures are off the wall, anything high up has come down and the cat has gone. He is probably still heading south.
"I've been in a few big quakes down in Southland, but nothing like this. It really flexed and the aftershocks were the other thing. They just kept hitting."
Mr McMullen drove to his school and said a quick check had revealed no major damage.
9.58am
Prime Minister John Key will fly to Christchurch to survey the damage after this morning's 7.1 magnitude earthquake.
9.45am
Amazing stories of residents being buffeted by this morning's earthquake.
Cashmere Hills resident Tony Stuart woke today to a crashing sound rumbling through his house as a massive earthquake hit Christchurch.
"It was the noise of the glass breaking that will remain with me. All I could hear was glass crashing and stuff dropping all over the place," he told NZPA.
9.32am
South Canterbury escaped with only minor damage from the 7.1 magnitude earthquake which struck near Christchurch early this morning.
Temuka, 18km north of Timaru, where a number of older brick and concrete buildings had been cordoned off for safety.
A Timaru District Council emergency first response team and building inspectors had been sent north to the Selwyn District, where the damage was worse, she said.
9.19am
Civil Defence Minister John Carter says it is very likely a state of emergency will soon be declared for Christchurch following discussions with authorities at the scene of today's massive earthquake.
9.17am
Civil Defence Minister John Carter has flown to the capital this morning, and Energy Minister Jerry Brownlee, a MP for Ilam, is already there as the National Crisis Management Centre in the Beehive has been activated.
9.15am
At least 20 roads had been damaged and some are impassable in parts of Christchurch after the massive earthquake which hit this morning.
8.37am
Christchurch Hospital reports two men have been seriously injured by the earthquake.
One man in his 50s is in a serious condition in intensive care at Christchurch Hospital after a chimney collapsed on him in the 7.4 magnitude earthquake, which hit at 4.30am today.
Another man, also in his 50s,was seriously injured by falling glass.
The main Christchurch Hospital is being inundated by residents arriving with broken limbs, bruises and cuts.
A spokeswoman, Michelle Hider, asked residents with minor injuries to go to 24 hour surgeries for treatment rather than the hospital.
The hospital is functioning well with a full staffing.
Early morning, the hospital switched to emergency power to keep operating theatres open.
8.36am
Power is back on in Kaiapoi and Shirley. But water cut remain cut for several hours.
8.35am
Timaru is also experiencing aftershocks. There are reports that a hotel in Temuka has been damaged by the earthquake which was centred 33km west of Christchutch.
7.49am
Police have just issued a stern warning to "criminals" after reports of looting in the central city, including Colombo St.
"Do not attempt to take advantage of this," said Detective Superintendent Dave Cliff. Police have sealed off part of the Christchurch CBD due to the level of damage sustained by the buildings and the very real risk of further collapses.
7.40am
Herald reporter, Jarrod Booker, on the scene in Christchurch has just filed an amazing interview with resident, Knee Doherty.
"We didn't even notice the movement as much as the noise. The back of the house is pretty much gone. All the house next door is gone. It was just a massive noise."
7.37am
Herald reader, Terry Whiting, tells nzherald.co.nz: "Our son in Christchurch says that all their furniture is lying on the floor, TV fallen of stand, PC on the floor, and they are sitting in their car, petrified, hoping for assistance."
7.30am
In an interview with NewstalkZB Mayor Bob Parker described the quake as "sharp, severe and terrifying."
7.27am
Mayor Bob Parker has just warned residents to conserve water after fears the water infrastructure of Christchurch may have been affected by the 7.4m magnitude earthquake.
He has told residents not to flush the toilet and to conserve water. There are fears the sewerage system may have been damaged. Engineers are checking the City infrastructure now.
7.19am
Civil Defence has activated the National Crisis Management centre in Wellington.
7.12am
Christchurch mayor Bob Parker and police have asked people to stay off the roads after reports emerging of damage to the roading network around the city.
Engineers will check the bridges on the Christchurch motorway network for damage after the 7.4 magnitude earthquake. There are also concerns about some of the area's bridges.
7.11am
Herald reader, Gayle Temple, sent us this eye witness account from the earthquake zone.
"We live in Ashburton and were woken to our house shaking and rolling. I have never been so scared in my life running from upstairs to get down where we hid under a table.
"We didn't know what to do having never experiencing anything like this in our lives the after shocks are still happening and I am still shaking. Lots of alarms were going off but no damage to our property or those around that we can see."
7.02am
Herald reader, Tony Metternich, reports feeling the quake as far away as Invercargill. It "was two minutes of swaying".
6.37am
Calls are flooding into police communications centres around New Zealand, causing problems for staff already trying to deal with the massive earthquake and aftershocks which have hit Christchurch and Canterbury.
A police spokesman asked residents to call police emergency numbers only in an emergency.
6.32am
The Orion power company is working to restore power after the massive 7.4 magnitude earthquake hit Christchurch knocked out electricity. A spokesperson for Orion said it appeared parts of rural Canterbury and Christchurch were without power. Orion has asked residents not to call in about the power since its lines are now jammed.
6.20am
Dr Mark Quigley is a lecturer in the Department of Geological Sciences at the University of Canterbury in Christchurch. He has just reported that witnesses told him the Avon River in Avonside overflowed its banks in places due to a surge in the river caused by the massive earthquake which hit Christhchurch at 4.30am today.\
He said there are large cracks in parts of the roads and gardens around Avonside - some measuring 20cm across and up to a metre deep.
Dr Quigley told RadioLive that the force of the quake had pushed up sand and dirt in mounds in parts of Avonside.
He will post pictures of the quake - when internet connectivity is restored to the city - on his website here.
6.11am
There are some power lines partially down on Avonside Drive, Christchurch.
6.10am
Civil Defence officials and officers from Christchurch City Council are meeting now to determine priorities after reports of damage around Christchurch caused by a 7.4 magnitude earthquake.
6.09am
First pictures are beginning to emerge from earthquake-hit Christhcurch.
This picture is currently being retweeted on twitter, apparently showing damage in central Christchurch. Click here
6.01am
Students are gathering in the main carpark of Canterbury University after being buffeted by the 7.4 magnitude earthquake which hit Christchurch at 4.30am today, which was then followed by a series of strong aftershocks.
A student reported that there were no injuries he could see and the University buildings appeared to have not sustained major damage.
6.00am
Police have announced they are investigating a possible case of looting on Colombo St after Christchurch was rocked by a 7.4 magnitude earthquake, but said they have no further details.
5.59am
Darfield, west of Christchurch and close to the epicentre of the earthquake, is experiencing rumbling earthquakes. Power is off in the town but a resident reported only minor damage after the quake, which measured 7.4 on the Richter scale, hit at 4.30am.
5.57am
A series of substantial aftershocks is still continuing to rock parts of Canterbury.
A resident in Ashburton reports a major shock hit around 5.50am. However, the town continues to have lighting and power. "We mainly had stuff knocked off shelves."
5.42am
There are reports of some buildings demolished in Victoria St, Christchurch after the magnitude 7.4 earthquake struck Christchurch and Canterbury.
Police have just asked residents to not travel into the CBD, saying that the older buildings in the central city have sustained damage and they are unsure if any further collapses may occur.
5.41
Reports of the earthquake are coming in from as far afield as New Plymouth and Invercargill.
The quake was centred 33km west of Christchurch but New Zealand residents are reporting feeling the earthquake or aftershocks hundreds of kilometres away.
View Christchurch earthquake in a larger map
