The story

Some of the miners at Utah's Crandall Canyon mine -- including one of the men trapped by Monday's cave-in -- apparently were concerned about working in the area of the collapse, a source told CNN.

The source, who requested anonymity, said the six trapped miners were working in an area called 7 Belt -- the deepest part of the mine.

A large hole being drilled in an effort to reach the men had bored through 1,644 feet of earth as of Friday night, officials said. A total depth of 1,886 feet is anticipated, said Richard Stickler, assistant secretary of the Department of Labor for mine safety and health. Read full article »

CNN's Vivienne Foley, Ed Lavandera and Gary Tuchman contributed to this report.

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