At least one Australian "family man" is among the Christchurch earthquake dead and the Australian government has warned the public to brace for more bad news.

Images show how one of Christchurch's tallest buildings, the Hotel Grand Chancellor, is on the verge of collapse.

Yesterday's quake - the death toll for which stands at 75 - may prove to be NZ's worst natural disaster.

Police say more than 100 people may have been lost in Christchurch's quake-ravaged Canterbury TV building, which they say is "unsurvivable". The official toll from yesterday's devastating quake stands at 75.

Massive earthquake damage in Christchurch means Kirifi Mila, the New Zealand soldier killed in Afghanistan last week, will be buried in Hamilton without a formal military farewell from his army mates.

Fifteen CTV staff are believed to have died when their central Christchurch building collapsed after yesterday's magnitude 6.3 quake, CTV chairman Nick Smith says.

At least 14 people are missing from two companies in the Pyne Gould building in Christchurch tonight.

A woman trapped in rubble left a harrowing message for her son, in which she said she didn't think she would survive.

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.

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.

Fletcher Construction says its residential repair programme in Canterbury as agent for the Earthquake Commission (EQC) is temporarily on hold.

Rescue personnel have been pulled back from the central city as the 26-storey Hotel Grand Chancellor building is on the verge of collapse.

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

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.

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

Rescuers have recovered and identified 55 bodies and are yet to identify a further 20 bodies from yesterday's earthquake in Christchurch.