The New Zealand police say no survivors were rescued overnight in the city of Christchurch, which was hit by a magnitude 6.3 earthquake on Tuesday.
Seventy-one people have been confirmed dead in the South Island city, and officials are reviewing the number of missing, which had initially been reported as more than 300.
The police say the last survivor was pulled out at three o'clock yesterday afternoon.
But Superintendent Russell Gibson says experts tell them there's no reason they shouldn't continue to find survivors, especially if they don't have crush injuries.
He says the police operation remains a rescue operation.
Police say they have returned to work at the collapsed Canterbury Television building, where about 100 people are believed to be trapped.
But rescue teams have pulled back from the Pyne Gould building in central Christchurch again this morning, because of concerns that continuing aftershocks are affecting the building's stability.
More than 20 people are thought to be trapped in the building, and yesterday a woman was pulled alive from the rubble.
At that stage, the Fire Service was saying that it had detected signs of life from up to four or five people in two separate locations in the building.
But there have been no further rescues at the site overnight
Paul Howison was on the third floor of the Pyne Gould Building when the earthquake struck.
"The floor just feel out from underneath me and the ceiling above, which is actually a slap of concrete, which is the fourth floor, came down and in a split second it was just horrendous, they say it was like a bomb going off and it was just like nothing I have ever experienced before."
So far 71 people have been confirmed dead and the Prime Minister John Key says the police will today begin releasing names of some of the 71 people who are confirmed dead.
But he says people should understand the number of dead is expected to rise.
We know that there are a number of sites where is it likely that we have suffered other fatalities, and it's a very tragic situation and it's a time of great agony for those families and of course other New Zealanders looking on.
Search and rescue teams are continuing to search for survivors and more teams from around the world are landing in Christchurch today.
The Fire Service's head of special operations Jim Stuart-Black says the help, which is coming from Australia, Singapore, Taiwan, Japan, America and the United Kingdom is much appreciated.
What it does is we can effectively cover greater areas of the city quicker. where we may find ourselves in a situation of having identified live victims, it means we can throw even more resource on that problem and we can commit the resource whilst also doing other tasks around the city.
Eighty percent of Christchurch is still without a normal water supply, although tanks are being deployed around the city.
Forty percent of the city remains without power and the chief executive of the Orion electricity company Roger Sutton says the underground power network is so badly damaged in some places it may never be repaired.
We haven't even got into our own mind a figure of how long it's gonna be for some of these customers. We know the joy and pleasure people get from having the jolly power on, so we are going to do our best to go back on as quickly as possible and clearly some customers are going to take weeks.
A Canterbury Medical Officer of Health says rivers are open sewers and people must take special care.
Alistair Humphrey says there are no reports of disease outbreaks in the city at this stage.
But he says people must be sure to keep their hands clean.
He says major infrastructure damage means drinking water will not be available for some time.
And, the need to conserve water means sewage will have to be buried deeply or transported away.
Two aftershocks measuring four or more in magnitude have rattled the city this morning.
GNS Science says a four point four magnitude aftershock was centered 10 kilometres south of the city, at a depth of six kilometres, while a magnitude four tremor struck 10 kilometres south-east of the city, at a depth of ten kilometres.
Christchurch residents are being asked to stay at home if they can and look after their neighbours.