Efforts to rescue 29 men trapped in a New Zealand coal mine face further delay after authorities said a new shaft to test air quality would need to be drilled before rescue teams could enter.
There has still been no contact with the miners since an explosion ripped through the colliery on the rugged west coast of New Zealand's South Island on Friday afternoon.
Rescuers have been unable to enter the mine due to the presence of gas, including methane, and tests conducted today showed the levels of gas were only slowly abating.
A new shaft will be drilled from the surface to enable additional air tests to be completed, a process which could take as much as an additional 24 hours, authorities said.
New Zealand rescuers have yet to make contact with the trapped miners.
The mayor of the Grey district, who briefed family members on the gas dangers earlier, said frustration was starting to show.
‘There's a little bit of anger, there's a little bit of despair. It was the most emotional meeting yet,’ Tony Kokshoorn said.
The explosion is thought to have been caused by methane gas, Pike River Coal chief executive Peter Whittall told a news conference in Greymouth, the nearest town to the mine on the South Island's west coast.
‘The air quality tests from the samples taken this morning have been inconclusive,’ Mr Whittall told reporters, adding testing was continuing.
District police commander Superintendent Gary Knowles said there was a ‘fine balance’ in deciding when to allow rescuers into the mine.
‘I'm not going to put people underground and risk further lives,’ he said.
The small size of the search area in the two-year-old mine and the time to plan and prepare while the air is checked meant the actual search itself would be quick, he said.
The miners include two Britons and two Australians.
New Zealand Prime Minister John Key said offers of help and support had flooded in from around the world.
Mr Whittall said underground communications were down, except for one emergency phone which rescuers had been calling constantly without anyone picking up.
But he stressed the miners might be trapped in an area away from the phone, or unwilling to venture from an area of safety to answer it.
‘It's quite conceivable that there is a large number of men sitting around the end of the open (ventilation) pipe, waiting and wondering why we are taking our time to get to them,’ he said.
The explosion is believed to have occurred about 1.5km along the mine shaft.
Two men escaped the mine in the moments after the blast yesterday, walking out of the main shaft, but they were unable to give rescuers the location of the others.
