New Zealand mine disaster timeline

All 29 miners trapped in a New Zealand mine are now feared dead after a second blast ripped through the pit.

Here is a timeline of the rescue attempt (times in GMT):

NOVEMBER 19

:: 0245: The men are trapped by a gas explosion at the Pike River Coal Mine in Atarau, on South Island.

NOVEMBER 20

:: 0500: A mission to locate the workers hampered by fears of a second explosion. It is not known if the men are alive or dead.

Tony Kokshoorn, mayor of nearby Greymouth, warns it could be days before it is safe enough for special teams to enter the mine.

:: 0600: Union representative Trevor Bolderson says chances of a second blast are high after initial readings are taken of the gas levels in the mine.

Foreign Office confirms two Britons are reported missing.

:: 0800: One of the missing Britons is understood to be Pete Rodger, 40, from Perthshire, Scotland, who emigrated to New Zealand two years ago to be closer to his mother and sister who live there. He was formerly an offshore oil engineer.

:: 1300: Second missing Briton is understood to be Malcolm Campbell, 25, originally from St Andrews in Fife.

Prime Minister David Cameron sends a text message to his New Zealand counterpart John Key saying: "I am thinking and praying for the best. I will make sure our diplomatic team help in any way they can."

:: 1700: It emerges that Prince William has also sent an email to Mr Key offering his support.

Twenty-four New Zealanders, two Australians, two Britons and one South African are confirmed inside the mine.

:: 1800: The parents of Mr Campbell say they are waiting in hope for news about their son. Malcolm senior, 50, and mother Jane, 45, say they have to keep hoping for good news, as do all the other parents of the trapped miners.

It emerges that Mr Campbell junior is due to marry his fiancee, Amanda Shields, 23, on December 18.

Mr Rodger's New Zealand-born girlfriend, Dianne Morris, writes on her Facebook site: "Just got to keep having positive thoughts."

NOVEMBER 21

:: 0300: Pike River Mine's chief executive, Peter Whittall, says latest tests on gases in the mine show it is still unsafe to launch a rescue operation.

Trevor Watts, who is leading a team of 30 men from New Zealand Mine Rescue, says his men are ready to deploy if there is a window of opportunity.

:: 1900: Russell Smith, one of two miners to escape the blast, describes being bombarded with a wall of dust and debris. "It wasn't just a bang, finish, it just kept coming, kept coming, kept coming," he says. He was pulled to safety by colleague Daniel Rockhouse and it took at least an hour for the two to walk out of the dust-choked tunnel.

A hole is being drilled from the mountain above down 500 feet to the mine to assess air quality and to lower listening devices.

:: 2300: Mr Key says: "We're going to get through this and do everything that we possibly can to get the men out alive."

NOVEMBER 22

:: 0300: It emerges that a hi-tech robot is being prepared to be sent into the mine to transmit pictures and take more measurements.

Police Superintendent Gary Knowles says: "The situation remains grave, given we've had no contact from the men for more than three days." But he insists: "We remain optimistic."

Mr Key says there is "every chance" the miners are still alive. They may have reached a pocket of oxygen flow, he says.

Mr Whittall says teams drilling a second borehole into the mine have reached a depth of 410ft (125m), but the operation has been slowed due to reaching hard rock.

:: 2140: Mr Knowles indicates hopes are fading over the fate of the men as he says it is too dangerous to send rescue teams into the damaged pit.

"This is a serious operation and the longer it goes on, hope fades and we have to be realistic," he tells the media.

The rescue effort also suffers a blow when the remote-controlled robot sent into the mine breaks down, requiring more advanced equipment to be flown in from Australia.

NOVEMBER 23

:: 0230: Mr Key warns the nation to prepare for the worst, saying police are planning for the possible loss of life following the blast.

:: 0600: Rescuers release footage of the explosion at the mine entrance.

Closed circuit TV footage shows a wall of white dust and stones surging from the entrance for 50 seconds as the underground blast rips through the mine.

:: 2130: Rescue teams say they are still unable to go into the mine because it is not safe.

NOVEMBER 24

:: Early hours: A drilling team which breaks through to the section of Pike River mine are greeted by a blast of potentially deadly gases.

:: 0404: Mr Knowles reveals a second explosion has ripped through the mine, and nobody is thought to have survived.

He says: "The blast was horrific - just as severe as the first blast.

"Based on the expert advice I have been given it's our belief there would have been no survivors."

Some family members who are told at the scene react by shouting, with others falling to the floor.

:: 0530: Addressing the nation, New Zealand's prime minister John Key says: "We are a nation in mourning.

"Where this morning we held on to hope, we must now make way for sorrow."