Updated

The man who led the government's investigation of the Sago mine tragedy in West Virginia will direct a similar probe of the Utah mine collapse that trapped six men earlier this month, officials said Thursday.

"MSHA's investigation will fully examine all available evidence to find the cause of the ground failure at Crandall Canyon mine and any violations of safety and health standards," MSHA chief Richard Stickler said in a statement.

The work will be led by Richard Gates, district manager in Alabama for the federal Mine Safety and Health Administration, who investigated the January 2006 Sago mine explosion that led to 12 miner's deaths in West Virginia.

At the Crandall Canyon mine in Utah, six miners became trapped more than 1,500 feet below ground after an Aug. 6 cave-in. Several test holes drilled to find them had found no evidence by Thursday that any of the men survived, but also no sign that they didn't.

Crews successfully drilled a seventh hole through the mountain and into the mine Thursday, said Capt. Kyle Ekker of the Emery County Sheriff's Office. Teams planned to send a robotic camera through the hole.

Searchers tried tunneling through the fallen debris to where the men were last working, but three rescuers died in another cave-in Aug. 16 and that effort was called off.

University of Utah seismologists insist the initial cave-in was violent enough to cause a 3.9 magnitude earthquake. The mine's co-owner, Murray Energy Corp., claims an earthquake caused the collapse.

Stickler said the investigation at Crandall Canyon would involve people who have no ties to MSHA's Western district, which oversees safety at the mine, 120 miles south of Salt Lake City.

They include Timothy Watkins, an assistant district manager in Kentucky who has ventilation and retreat mining experience; Gary Smith, a supervisor in Pennsylvania who has roof-control expertise; and Joseph O'Donnell, who is based in MSHA's district office in Alabama. Gates, who will lead the group, has been with the agency for 19 years.