The Government has declared a national state of emergency after yesterday's 6.3 magnitude earthquake in Christchurch.

Christchurch Mayor Bob Parker says emergency cash grants will be made available for victims of yesterday's quake.

Cabinet will hold an emergency meeting at 9.30am to decide whether to declare a national state of emergency, Prime Minister John Key says.

Rescue workers are having to leave bodies in the streets of Christchurch as they focus on trying to save survivors of yesterday's devastating 6.3 magnitude earthquake.

The official death toll from yesterday's earthquake in Christchurch has been revised to 38, but there are fears it could reach as high as 300 as rescuers uncover more bodies in the rubble.

Between the giant rubble littering the rain-drenched Colombo St, police pull another dead body and lay it down on a black tarpaulin.

Five World Cup games and two quarterfinals scheduled for Christchurch are in jeopardy after yesterday's big quake.

Prime Minister John Key flew into Christchurch to what he says were scenes from a horror movie.

North Island hospitals are receiving Christchurch earthquake victims and plan to send specialists to help in the devastated city.

The earthquake that struck Christchurch during lunch hour yesterday was an aftershock seismologists hoped would never come.

Hope amongst the rubble of a collapsed multi-level office block on Madras Street as a woman buried by rubble is dug out alive after Christchurch's devastating earthquake.

Residents of the town at the epicentre of today's devastating aftershock have told of terrifying ordeals as the ground crumbled around them.

Several appeals have been launched to help Cantabrians following today's devastating earthquake. ANZ launched an appeal and announced it would make the first donation, $1 million.