Three coal miners were killed and a fourth escaped injury when a mine shaft collapsed Wednesday one-half mile beneath the earth's surface, authorities said.

The three miners were crushed when support beams gave way in the Cumberland Valley Contractors mine, but the fourth worker ran from the cave-in and was unscathed, said firefighter David Smith.The four miners were in a shaft 2,600 feet underground when the collapse occurred at 3:20 p.m. EST, Smith said.