Bodies are littering the streets, say rescue workers in Christchurch
At least 75 dead but toll 'will be considerably higher than that'
Race against time to free estimated 100 people under the rubble
More than 12 large buildings completely collapse, 15 victims die in one alone
PM John Key declares national emergency as he says: 'It's heartbreaking'
Famous Christchurch Cathedral destroyed
A victim of the Christchurch earthquake is frantically phoning rescuers from beneath the rubble, as the full scale of the destruction in the New Zealand city emerged.
More than 30 victims are trapped in the Pyne Gould building in the city centre, after the quake which has left bodies littering the streets and killed at least 75 people - with local experts fearing between 200 and 300 may have died
The building is one of more than a dozen that have completely collapsed, as rescue workers gave harrowing accounts of 'bodies littering the streets'.
Anne Voss, who is trapped and injured in the Pyne Gould office block, told the Channel 7 TV station that she can’t see her colleagues but she knows they are on the other side of the building.
'I have no idea what condition they're in, but I can hear them at times yelling for help.'
Get me out: Rescuers on top of Christchurch's Pyne Gould building where Anne Voss is trapped with 30 others
I'm sitting under a desk and the ceiling has collapsed on the desk. I’ve got no water or food, I know I'm bleeding. I can feel the ground is quite wet. I can't see. I think they know I'm here. I keep knocking and shouting "help".'
Ms Voss said friends and family have been phoning her to keep her spirits up, as rescuers try to clear the rubble from the office block.
Earlier, she had made it through to the radio station TV3. She told them: 'I rang my kids to say goodbye' during the quake.
'It was absolutely horrible. My daughter was crying and I was crying because I honestly thought that was it.
'You know, you want to tell them you love them don't you?'
The quake was the second major shock to hit the city of 350,000 in five months, although it caused far more destruction than the first.
More than 100 people are thought to still be trapped in the rubble and 300 victims are missing.
'There are bodies littering the streets, they are trapped in cars, crushed under rubble and where they are clearly deceased our focus ... has turned to the living,' Police Superintendent Russell Gibson said. 'We are getting texts and tapping sounds from some of these buildings and that's where our focus is.
'I know the figure of 65 (killed) has been mentioned (by Prime Minister John Key). It will be considerably higher than that.'
Firemen who had lowered a camera into an air pocket in the rubble of the Christchurch TV building believed that at least 15 people were still alive. But it was later reported that all 15 had died of asphyxiation, after rescue workers started lowering food and water to the victims.
The building was one of the worst-damaged in the earthquake and before the discovery of the 15, a number of bodies have already been brought from the wreckage.
A Canadian woman, Carole Young, wept as she told how she and her husband Ross had a narrow escape from death as debris rained down around them while they were on a tour of Christchurch cathedral.
'The way it was all coming down as we fled...it reminded me of 9/11,' said Mrs Young. 'It was all tumbling down around us.
'We know that people died in there so someone was looking after us.'
Mall worker Tom Brittenden told of how he had helped pull victims from the rubble in the immediate aftermath of the quake.
'There was a lady outside we tried to free with a child,' he told local radio. 'A big bit of concrete or brick had fallen on her and she was holding her child. She was gone. The baby was taken away.'
Military units patrolled near-empty streets disfigured by the huge cracks and canyons
Prime Minister John Key declared a national emergency and described himself as 'a son of Christchurch' He said: 'There are no words that can spare our pain. We are witnessing a violent and ruthless act of nature.'
The disaster zone is 13 hours ahead of the UK. Dusk fell at around 8.56pm local time last night and dawn broke at around 6.30am - 5.30pm UK time - meaning rescuers faced almost 10 hours of darkness as they battle to save those still buried in the ruins.
'It is just a scene of utter devastation,' said Mr Key, who arrived in the city within hours of the quake striking at 12.51pm with its epicentre in the suburb of Lyttelton.
He said the death toll may rise, and added: 'We may well be witnessing New Zealand's darkest day.'
Christchurch Mayor Bob Parker declared a state of emergency and ordered people to evacuate the city centre.
'Make no mistake — this is going to be a very black day for this shaken city,' he said when asked about possible deaths.
The Queen today said she was 'utterly shocked' by the disaster in a message of support sent to New Zealand prime minister Key.