Fears that dangerous mine gas could trigger a second explosion stalled rescue crew search efforts on Saturday at the New Zealand coal mine where 29 workers are missing nearly a day after a powerful gas blast struck deep underground.
Two dazed and slightly injured miners stumbled to the surface hours after the blast shot up the 354-foot-long ventilation shaft at the Pike River mine on Friday. Video from the scene showed blackened trees and light smoke billowing from the top of the rugged mountain where the mine is located, near Atarau on New Zealand's South Island.
Pike River Mine Ltd's chief executive Peter Whittall said it was not known if the men were alive because nothing had been heard from the 16 employees and 13 contract miners since Friday's explosion at the mine. Repeated attempts to contact the 29 men had failed.
"We can't risk sending men into the mine until we know exactly what (the quality of the gas) is," he said.
A coal-gas explosion was the most likely cause of Friday's major blast, Whittall said.
"There could be another explosion," said mine safety expert David Feickert, who noted that officials don't yet know what caused the original ignition, and rescuers will enter the mine only when it is safe.