WELLINGTON (AFP) – Desperate efforts to reach at least 27 coal miners missing after an explosion tore through an underground mine in New Zealand stalled Friday as fears of another blast frustrated rescue attempts.

Police said the explosion at the coal mine on the South Island's west coast appeared to have crippled the mine's ventilation system but locals said they were drawing hope from the rescue of 33 miners in Chile last month.
Two miners survived the blast at the Pike River coal mine but there had been no contact with any others, the mining company's chief executive said.
Police said a specialist mine rescue team was at the scene but could not go underground because the blast knocked out power to the mine's ventilation pumps, meaning there was a danger they could ignite trapped gases.
“There's been an explosion, they don't know what's caused it, they can't just go charging in there and put other people at risk,” police spokeswoman Barbara Dunn told Radio New Zealand.
The ventilation system would also normally supply air to any surviving miners, and police said they were concerned that it had been compromised by the power outage.
Reports said families of the miners were gathering at the site, at the heart of New Zealand's coal industry about 50 kilometers (30 miles) northeast of Greymouth, as rescuers prepared to work through the night.
Grey District mayor Tony Kokshoorn said the rescue was difficult and could take days.
But he said the experience of Chile's miners, who were successfully brought to the surface last month after surviving more than two months in a tunnel below the Atacama desert, was a source of inspiration.