AFP, WELLINGTON: Rescuers dug frantically for bodies and people trapped after a major 6.3 earthquake caused "multiple" deaths in New Zealand's second city of Christchurch Tuesday, crushing buildings and vehicles.
Thousands of panicked and tearful residents thronged the city's streets after the quake struck at lunchtime, just six months after a 7.0-magnitude tremor shattered buildings but did not claim any lives.
Police warned the latest earthquake had left people dead. One office building housing 200 workers had collapsed, while Christchurch Cathedral's spire tumbled.
Local station TV3 said dead bodies had been pulled from a hostel, and a tourist had been crushed to death in a van. All flights across the country were briefly suspended after Christchurch control tower was damaged.
Declaring a state of emergency, Christchurch mayor Bob Parker said: "Everybody needs to understand that this is going to be a very black day for this severely shaken city.
"I've had reports of buses that are trapped under fallen buildings, car park buildings that have taken significant damage, collapsed or partially collapsed. In some of the inner-city streets we have people trapped in buildings."
As several strong aftershocks pummelled the stricken city of 340,000, which has endured continuous tremors since September's disaster, bleeding and limping survivors emerged from damaged buildings.
Christchurch airport was closed and The Press building, a centre for newspapers, was badly damaged. Reports said trapped survivors were desperately phoning their families from the wreckage.
"The details that we have are extremely sketchy. But the worry and fear of course is that this earthquake has taken place at a time when (residents) were going about their business," said Prime Minister John Key.
"It is a very populated time with people at work, children at school," he warned. "Sadly I cannot rule out whether there have been fatalities."
The quake struck at 12:51 pm (2351 GMT Monday), five kilometres (three miles) from Christchurch at a depth of just four kilometres.
Emergency services said it was more damaging than September's quake, which struck before dawn with most people safely at home.
"The shake has been a lot worse, maybe not in intensity but as far as damage is concerned, and there are numerous people trapped," a fire service spokesman told Radio New Zealand.
Cars were buried under rubble and roads buckled as the tremor opened ruptures in the ground. Police feared multiple deaths, including in two buses that were crushed by falling debris.
"Multiple fatalities have been reported at several locations in the central city, including two buses crushed by falling buildings. A doctor and emergency services are attending," a police statement said.
"Other reports include multiple building collapses, fires in buildings in the central (city) and persons reported trapped in buildings."
On September 4, Christchurch suffered the most destructive quake to hit New Zealand in 80 years when a 7.0-magnitude tremor damaged 100,000 homes, leaving a clean-up bill estimated at NZ$4.0 billion dollars (US$3.0 billion).
The city remained under a state of emergency for weeks with police cordoning off the centre for fear of collapsing buildings, as thousands of aftershocks hit the region.
At the time, authorities gave a clean bill of health to Christchurch's 36,000-capacity AMI stadium, one of the venues for the rugby World Cup starting in September.
New Zealand sits on the "Pacific Ring of Fire", a vast zone of seismic and volcanic stretching from Chile on one side to Japan and Indonesia on the other.
