Christchurch a 'war zone' after quake
Wellington - A strong earthquake killed at least 65 people in New Zealand's second-biggest city of Christchurch, with more casualties expected as desperate rescuers picked through rubble to find people trapped in toppled buildings.
It was the second quake to hit the city in five months.
"We may well be witnessing New Zealand's darkest day...The death toll I have at the moment is 65 and that may rise," New Zealand Prime Minister John Key told local TV.
The 6.3 magnitude quake struck at lunchtime, when the streets and shops were thronged with people and the offices were still occupied.
Christchurch's mayor described the city of almost 400 000 people as a war zone.
"There will be deaths, there will be a lot of injuries, there will be a lot of heartbreak in this city," Mayor Bob Parker told Australian TV by phone.
Helicopters dumped giant buckets of water to try to douse a fire in one tall office building. A crane helped rescue workers trapped in another office block.
"I was in the square right outside the cathedral - the whole front has fallen down and there were people running from there. There were people inside as well," said John Gurr, a camera technician who was in the city centre when the quake hit.
Authorities ordered major hospitals up and down the country to make room for quake victims. There were reports of a shortage of ambulances.
"A lady grabbed hold of me to stop falling over...We just got blown apart. Colombo Street, the main street, is just a mess...There's lots of water everywhere, pouring out of the ground," Gurr said.
Emergency crews picked through the rubble, including a multi-storey office building whose floors appeared to have pancaked on top of each other.
Silt, sand and gravel
Christchurch is built on silt, sand and gravel, with a water table beneath. In an earthquake, the water rises, mixing with the sand and turning the ground into a swamp and swallowing up sections of road and entire cars.
TV footage showed sections of road that had collapsed into a milky, sand-coloured lake right beneath the surface. One witness described the footpaths as like "walking on sand".
Unlike last year's even stronger tremor, which struck early in the morning when streets were virtually empty, people were walking or driving along streets when the shallow tremor struck, sending awnings and the entire faces of buildings crashing down.
Police said debris had rained down on two buses, crushing them, but there was no word whether anyone had been killed or injured.
The quake hit at 12:51 (23:51 GMT) at a depth of only 4km, according to the US Geological Survey.
"It's huge, it's just huge," a priest told a TV reporter outside the remains of the city's stone cathedral, part of which had been reduced to a pile of large sandstone blocks.
"I just don't know whether there are people under this rubble," he said, before he appeared to add in a quiet voice: "I think so."
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