Declaring a national state of emergency is an option when a disaster or other event is or is likely to be of such severity that it is beyond the resources of the local Civil Defence groups.

Six people have today been arrested for theft and burglary in the quake-hit Christchurch CBD.

Police have abandoned all hope of finding survivors at the collapsed Canterbury TV building in central Christchurch, with a police chief saying he was "100 per cent" certain those trapped inside were dead.

All Christchurch AMI Insurance branches have been forced to close due to quake damage.

Search and rescue teams could continue looking for survivors for a second night following yesterday's Christchurch earthquake, Civil Defence national controller David Coetzee says.

There are genuine fears that the Crusaders will have to find a new home for the remainder of Super Rugby season.

In an emotional reunion, a woman trapped for more than 25 hours in a cramped, dark space in the destroyed PGG building has finally been rescued and reunited with her worried husband.

Christchurch's Rolleston prison will be cleared to create beds for the influx of rescuers into the city.

Earthquake damage in the small town nearest to the epicentre of Tuesday's 6.3 magnitude quake.

Aerial photos reveal the damage to buildings and shows rubble lining the streets of Christchurch.

Hundreds of specialist search and rescue personnel from around the world are arriving in Christchurch.

Rescue services have stopped work at CTV and are now focusing on the Pyne Gould building, where as many as 50 people are thought to still be alive.

A man who has more than a dozen close friends and colleagues missing in earthquake-devastated central Christchurch says all he can do is wait and hope they are still alive.

Track the aftershocks rattling Christchurch in the wake of the shallow magnitude 6.3 earthquake.

IAG, the ASX-listed insurer that owns State Insurance and NZI, says the latest earthquake will cost it up to A$40 million.

The Government has declared a national state of emergency after yesterday's 6.3 magnitude earthquake in Christchurch.

The New Zealand Defence Force aide NZ Police in affected areas around Christchurch.

Christchurch Mayor Bob Parker says emergency cash grants will be made available for victims of yesterday's quake.

Compare photos of some of Christchurch's hardest hit buildings from before and after the earthquake.

Images record the shocking aftermath of the magnitude 6.3 quake around central Christchurch.

Cabinet will hold an emergency meeting at 9.30am to decide whether to declare a national state of emergency, Prime Minister John Key says.

The Crusaders have suffered personal loss as a result of the Christchurch earthquake.

Rescue workers are having to leave bodies in the streets of Christchurch as they focus on trying to save survivors of yesterday's devastating 6.3 magnitude earthquake.

The city remains in ruins as rescue workers search through the night for survivors of the Christchurch earthquake.