CHRISTCHURCH: New Zealand rescuers worked frantically through the night Wednesday to reach trapped survivors after a catastrophic earthquake left nearly 400 people dead or missing in Christchurch.

Prime Minister John Key, declaring a national emergency after New Zealand’s worst natural disaster in 80 years, said the region around the country’s second-largest city had suffered “death and destruction on a dreadful scale”.

Rescuers had to amputate limbs from survivors to free them from smouldering ruins of buildings reduced to debris in minutes, while dazed survivors were plucked from the rubble in a desperate overnight rescue mission.

Christchurch resident Tom Brittenden said he saw a woman die with her baby in her arms when she was hit by falling debris in the city’s Cashel St Mall.

Her baby survived but she was killed instantly.

“We tried to pull these big bricks off her but she was gone,” he told the Christchurch Press.

Rescuers had recovered 75 bodies since the 6.3-magnitude quake struck at lunchtime Tuesday, and about 300 people were still missing, officials said.

The quake was the deadliest to hit New Zealand since 256 people died in a 1931 tremor, and it came six months after a 7.0-magnitude quake weakened buildings in Christchurch but miraculously resulted in no deaths.

The latest tremor toppled many buildings and left central Christchurch strewn with debris. The city’s landmark cathedral lost its spire. Dozens of aftershocks rocked the city Tuesday and overnight, hampering rescue efforts.

Police Superintendent Russell Gibson warned that the toll was certain to rise as more than 500 emergency workers combed through shattered buildings, listening out for any signs of life.

“There is incredible carnage right throughout the city,” he told Radio New Zealand.

“There are bodies littering the streets, they are trapped in cars and crushed under rubble.”

Most of the city remained without power and Gibson said rescue crews working through the night had freed 20-30 people, some at desperate cost.

“It’s quite amazing, we have some people we’ve pulled out and they haven’t got so much as a scratch on them, we’ve had other people where we’ve had to amputate limbs to get them out,” he said.

Gibson said rescuers were going door to door through the city centre, with efforts concentrating on two city centre office buildings where survivors had managed to communicate with them.

“We are getting texts and tapping sounds from some of these buildings and that’s where the focus is at the moment,” he said.

However, fire service national commander Mike Hall said his officers had incorrectly reported that 15 people had been pulled alive from a collapsed six-storey office block.

“I have since been advised that it was a false report and that it is not true,” he told TVNZ, while police confirmed that no survivors had yet been recovered from the collapsed Canterbury TV building.

Prime Minister Key, who has described the disaster as possibly “New Zealand’s darkest day”, said: “No words that can spare our pain. We are witnessing the havoc caused by a violent and ruthless act of nature.”

Twenty-four Japanese citizens were among the missing, including 11 foreign-language students, Japanese reports said.

Japan, Australia and the United States were among countries sending rescuers to help.

Britain’s Queen Elizabeth, who is New Zealand’s head of state, said she was “utterly shocked” while US President Barack Obama offered his “deepest condolences”, as expressions of sympathy poured in from around the globe.

Seismologists said that despite being smaller, the latest tremor was more destructive than the September quake because it was nearer to Christchurch’s centre and much closer to the earth’s surface.

New Zealand sits on the “Pacific Ring of Fire”, a vast zone of seismic and volcanic activity stretching from Chile on one side to Japan and Indonesia on the other.