It was a devastating turn for the families of the six men trapped in the Aug. 6 collapse at the Crandall Canyon mine and for the relatives of those trying to rescue them. It's not known if the six are alive.
All rescue workers were evacuated from the mine Thursday evening and work underground was stopped. Asked if the search would be suspended, "that's something to be determined," said Rich Kulczewski, a U.S. Department of Labor spokesman.
The cave-in at 6:39 p.m. was caused by a mountain bump in which pressure can force chunks of coal from walls of the mine with great force. Seismologists say such a bump caused the Aug. 6 cave-in that trapped the six men more than 3 miles inside the central Utah mine. That led to the frenetic effort by rescuers to dig through the mine toward the men and drill narrow holes atop the mountain in an attempt to learn their whereabouts and perhaps drop down food and water.
It was not immediately clear where the rescuers were working or what they were doing when Thursday's bump occurred.
Underground, rescuers had advanced only 826 feet in nine days. Before Thursday's cave-in, workers still had about 1,200 feet to go to reach the area where they believe the trapped men had been working.
Mining officials said conditions in the mine were treacherous, and they were frequently forced to halt digging because of seismic activity.
A day after the initial collapse, the rescuers were pushed back 300 feet when a bump shook the mountain and filled the tunnel with rubble.