SALT LAKE CITY, Aug. 18 (UPI) -- Rescuers received no response Saturday when they signaled six miners who have been trapped in a Utah coal mine for almost two weeks.
All other operations at the Crandall Canyon Mine were suspended for four hours, The Salt Lake Tribune reported.
"We listened by microphone and also monitored the vibrations (in the mine) to determine if there was any sign (of life)," Richard Stickler of the U.S. Labor Department told reporters. "We did not detect any sign from the miners underground."
The drillers bored a fourth hole in the cavern where the six miners were believed trapped. Three previous holes yielded no sign of the men, alive or dead, The Salt Lake Tribune reported Saturday.
Underground attempts to reach the miners were suspended indefinitely Friday, a day after a second tragedy at the Crandall Canyon Mine killed three rescue workers and injured six others.
“We don't want to close the door and say no one can ever go in underground," said Kevin Stricklin, who oversees coal mines for the federal Mine Safety and Health Administration. "But we need to suspend it until we're confident that we won't have another situation like we did."
Two miners and a mine safety inspector died Thursday when pressure inside the mountain blew out 60 feet of wall, spraying the rescuers with coal and rock. Fellow rescue workers dug with their hands through 5 feet of coal to reach them, mine officials said.
Congressional leaders have promised hearings on the mine collapse. Sen. Patty Murray, D-Wash., who heads a subcommittee on workplace safety, said she would "conduct a comprehensive investigation into the causes of this tragedy, the handling of the response, and the ways we can improve mine safety and rescue efforts across our nation."
