NZ mine bore hole shows high gas levels
Rescuers trying to reach 29 men trapped in a New Zealand coal mine say a bore hole has shown high gas levels and little oxygen near where the men are believed to be.
Police Supt Gary Knowles, co-ordinating the rescue effort, said it was still not safe to send in rescue teams.
Two robots have been sent into the mine and a third is on its way, a news conference was told.
There has been no contact with the miners since an explosion on Friday.
Supt Knowles said air samples from the bore hole showed high levels of carbon monoxide and methane and low levels of oxygen.
He said the samples had been sent away for analysis.
Relatives of the missing men - 24 New Zealanders, two Australians, two Britons and a South African - are facing an agonising wait for news, but officials say the risk of a secondary explosion at the Pike River mine remains high.
Supt Knowles told reporters that the first robot to be sent into the mine - which earlier stalled after hitting water - had now gone 1km into the tunnel and sent back images of a miner's helmet with the lamp still illuminated.
A second robot was also now in the mine and a third would soon be arriving from Australia, he added.
New Zealand Prime Minister John Key has warned the nation to prepare for the worst as hopes fade that all the men have survived.
The explosion was so powerful it broke surface vents and blasted dust across nearby valleys.
"We hope and pray that the missing men are alive and well," he said in a sombre address to parliament.
"Although we must stay optimistic, police are now planning for the possible loss of life."