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Gisborne residents emerged from a nervous night as the first light touched the city today, revealing a city centre in lockdown, collapsed buildings and shattered glass.
Outside the battered business district - where people last night reported the shockwaves from a 6.8 magnitude quake roaring down on them like a train - they were collecting together their lives and possessions.
Many described the quake that hit just before 9pm, as a series of sharp shocks, followed by a lull then more shocks.
The quake was centred 50km offshore, southeast of Gisborne and 40km deep in the Hikurangi Trench - a subduction zone where the Pacific tectonic plate is being dragged under the Australian plate on which the East Coast sits.
Three buildings, including a block of apartments and two shops, collapsed, roofs caved in, water tanks and winery vats burst, parapets crashed to the ground and gaping holes opened up in roadways.
By the early hours of today no deaths or serious injuries had been reported and Police Commander Waata Shepherd said police had diverted people from the city centre and the business area was in lockdown.
But some Gisborne residents said they were still in shock from the rocking and jolting that seemed to go on for many minutes.
The quake was felt strongly in Wellington, Blenheim and Nelson and tremors were reported further down the South Island including Christchurch, Dunedin and Hokitika on the west coast.
Civil Defence Minister Rick Barker, who was in Hastings last night, was driving to Gisborne this morning to inspect the damage.
Mr Barker was warned - two years ago to the day - of the need for better computer modelling of the Hikurangi subduction zone as a trigger for tsunami. Scientists estimated that a significant tsunami at Gisborne would kill 2100 people and injure 5000.
Last night, people milled around in the streets and Gisborne mayor Meng Foon warned them that if a second quake stuck, they should head for the hills, in case there was a tsunami. ,
GNS scientists have warned a tsunami may be triggered by an underwater landslide or a "moderate" earthquake of 6.5 magnitude or larger.
GNS duty seismologist Warwick Smith said last night he also expected damage to be reported in Wairoa, Napier and Mahia, but the 6.8 tremblor had not been not strong enough create a tsunami.
But that did not stop residents rushing for the hills last night, as electricity supply was lost to most of the city. Some businesses, such as supermarkets and the Odeon Cinema resorted to generators, and Gisborne hospital lost power for 40 minutes.
In the city centre, the Gisborne Herald reported the most extensive damage was the collapse of the Bernina Sewing Centre roof, while a large parapet crashed through the roof of the Hallenstein building in the main street.
The Pencil Gallery on the corner of Grey St and Gladstone Road was damaged, and the veranda of Mitchells Camera House and the Health 2000 shop collapsed.
There were some minor fires reported, and a large hole appeared in Ormond Road, a major city street.
The manager of the Pak'n Save supermarket, Hamish Walton said he believed the stock losses from shelves of goods thrown in the aisles would be in the tens of thousands of dollars.
Montana's Lytton Road winery site - with the nation's largest winemaking capacity - was reported to have high-priced chardonnay running along the ground as up to 10 tanks were ruptured.
Other tanks - including water tanks at Gisborne's hospital - were also reported to have failed in the quake: "The water tanks on the hillside and on the roof have been damaged," said a spokesman.
Police said homeowners reported damage to hotwater cylinders which were not adequately fixed in place.
Gisborne District Council spokesman Vance Walker said relatively light damage was reported in terms of utilities, gas, water, sewage pumping stations.
Murray McPhail, who has a property at Makauri, about 10km from Gisborne city, said he could see waves in his swimming pool as the quake shook.
"You could just about surf on it," Mr McPhail told NZPA.
"Stuff come out of cupboards, bottles fell off walls, ornaments fell. "It was pretty violent. It was certainly a decent shake."
Gisborne resident, Catherine Watson said everyone was swaying as they stood in doorways: "Smashed glass everywhere, frames, ornaments smashed and on the floor, wine everywhere. Food has fallen off all the shelves in the pantry.
"Water pipes have burst so flooding all through the house.
"Everyone is driving out of town and the streets are all backed up with cars," she told the Dominion-Post newspaper. "It's terrifying".
- NZPA