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HUNTINGTON, Utah - Rescuers in Utah have suspended their effort to dig a tunnel to search for six trapped coal miners after a major cave-in killed three rescue workers and injured another six.
"We have suspended indefinitely the underground portion of this rescue effort," Richard Stickler, head of the federal government's Mine Safety and Health Administration, said.
He said rescuers would continue to drill bore holes through the top of the mountain to find the miners, who have not been heard from since a collapse on Aug. 6.
If the miners were found, a larger hole would be drilled in from the surface in a long, slow effort, Stickler said.
One of those killed and one seriously injured yesterday's collapse were federal employees, Stickler said.
"Yesterday we went from a tragedy to a catastrophe," said Utah Gov. Jon Huntsman outside the Crandall Canyon mine as he called for new efforts to make mining safer in his state and the country.
The cave-in was called a "mountain bump" -- an eruption of rock and coal under pressure from overhead rock as drilling removes surrounding rock and material shifts.
Seismologists at the University of Utah said they recorded waves from the bump "consistent with further settling and collapse within the mountain."
It remains unclear what caused the first collapse. Owner Robert Murray has said it was triggered by an earthquake; geologists say it was not.
Controversy also rose over reports that the miners were engaged in dangerous "retreat mining" when the shaft collapsed. Murray has denied such a technique was being used.
Retreat mining involves supporting a mine's roof with a column of coal, then removing that pillar and allowing the shaft to collapse as miners move to safety.
The Crandall Canyon Mine is on a high desert plateau some 225km south of Salt Lake City, in what is known as Utah's "castle country" because of the towering rock spires that dot the rugged landscape.
Central Utah has long been rich not just in coal deposits, but also the great fortunes and deep despair that come with pulling it from the ground. Monuments and museums to past tragedies mark the roads and towns in the center of the state.
The list of accidents stretches back at least to May 1900, when 200 men were killed by an explosion in the Winter Quarters Mine, one of the worst mining accidents in US history.
- REUTERS
