Christchurch: The devastating earthquake that rattled New Zealand's second largest city Tuesday claimed 98 lives, while a total of 226 people were missing Thursday with least hope for any survivors beneath the tonnes of rubble of wrecked buildings.

The 6.3-magnitude quake hit the central city of Christchurch, the country's business hub, at 12:51 p.m. on Tuesday when the streets and office buildings were packed with people.

Prime Minister John Key Thursday confirmed the number of victims 98 with at least 92 bodies kept in a temporary morgue set up by police in Christchurch.

Key told Prime News that the toll had gone up since earlier Thursday and is likely to rise further, the New Zealand Herald reported.

The list of missing stands at 226. No one has been rescued alive from the rubble of the ruined city since Wednesday.

According to Canterbury District Commander Superintendent Dave Cliff, the rescue efforts were focussed on finding survivors using a 'process involving sniffer dogs, acoustic testing - looking for any sound - along with cameras which are used to place within the rubble itself to look for any sign of life'.

"If we find a body but we can't recover it quickly, we will carry on. This is very much an operation around rescue, it's looking for the living," he was quoted as saying.

Of the missing, police were working to separate those who were likely trapped under buildings and those who were likely just out of town.

Up to 122 people in the Canterbury TV (CTV) station building were believed to be missing or unaccounted for, including more than 80 students and staff from King's Education Ltd, housed in the CTV building.

Police were certain that no one was alive in the CTV building, with the five-storey building catching on fire after it had been flattened by the quake on Tuesday.

The figure had been updated Thursday morning when 90 students and staff were said to be missing or unaccounted for. The institute's website said among those missing, nine were staff, 10 were Japanese student.

There was also no chance of survivors at the Christ Church Cathedral buildings and police estimated between 16 and 22 people were killed by falling rubble there.

Rescue work at the site was halted for safety reasons as the nearby Hotel Grand Chancellor, one of the city's tallest buildings, was on the verge of collapse, the report said.

Though the hotel survived several aftershocks, including a 4.1-magnitude shake just after midnight past Wednesday.

Prime Minister Key said an 'enormous recovery job' lay ahead and the government was working on a financial package for those affected by the quake.

Health authorities said Thursday that 164 people had been admitted to hospital, most with serious injuries, 431 treated at the emergency department and up to 2,000 seen for minor injuries at medical centres around the city, DPA reported.

The government was beginning to look at financial costs, with Key not ruling out speculation that total damage could be as high as $12 billion.

On Wednesday, the New Zealand government declared a national state of emergency for the first time in the country's history.

Civil Defence Minister John Carter said on Wednesday that the declaration of a national emergency reflects the likelihood that Tuesday's quake may prove to be New Zealand's worst natural disaster.

In 1931, an earthquake hit New Zealand's northern Napier city, killing 256 people. But Carter said until the toll and damage from Tuesday's quake was confirmed, "it's difficult to make those sorts of comparisons".