Police have delayed releasing the names of those confirmed dead and for whom there are serious concerns.

There is no possibility of survivors in the rubble of the Christchurch Cathedral, police said this afternoon.

Police and security staff are worrying about the possible further collapse of building facades.

Personnel at the PGC building in Christchurch have switched their focus from trying to find survivors to recovering the dead, the company says.

Rescuers have found no survivors at two Christchurch CBD buildings where signs of life were reported this morning, the Fire Service says.

Search and rescue staff are moving into the suburbs of Christchurch looking for the dead and injured from Tuesday's earthquake. The official death toll this morning stands at 72.

Prime Minister John Key has not ruled out imposing an earthquake levy similar to the flood levy brought in Queensland.

Hope is fading for hundreds of people missing for a second night after the Christchurch earthquake.

Their task is to enter highly restricted and prohibited areas, putting their lives on the line to save others.

The lost English tourist spotted by a helicopter last night in the Kahurangi National Park says he can't describe the relief he felt when he was found.

The English tourist found last night in the Kahurangi National Park had become disoriented and confused the route he was on for another.

A large search is underway for a missing 30-year-old English tourist, tramping in Kahurangi National Park west of Nelson.

The 33 miners rescued from inside a Chilean mine last year had considered suicide and cannibalism, it has emerged.