Federal and state investigators yesterday continued their probe into an underground mine collapse that killed a 49-year-old coal miner in Preston County, W.Va.

The accident was reported at 2:22 p.m. Friday at the Whitetail Kittanning Mine in Fellowsville, about 100 miles south of Pittsburgh. The mine is owned by Alpha Natural Resources, headquartered in Abingdon, Va.

Ted Pile, spokesman for Alpha Natural Resources, said the victim was a "miner operator" running a remote-control machine that carves coal from the walls of the mine. He was standing near the machine when a massive rock "about the size of a vending machine" unexpectedly broke from the right side of the mine "and pinned him against a shuttle car."

The cause of death was "crushing injuries," he said.

Mr. Pile said it was company policy not to release the names of accident victims, but that company counselors were with the miner's wife and three children last night. He did not know what town the family lived in.

The victim had been a coal miner for 25 years, 11 of them in the Whitetail Kittanning Mine, which Alpha Natural Resources acquired from Coastal Coal Co. in 2003.

"We operate 67 mines, probably more than any other company in the United States," Mr. Pile said.

"Any day when there's an accident is a sad day," he said. "Our miners work very, very hard on safety awareness and training, and up until this point we had an excellent safety record this year."

It is the first fatality at an Alpha Natural Resources mine this year, he said.

The victim was rushed to Preston Memorial Hospital, where he was pronounced dead on arrival. A member of the Preston County coroner's office said he was then transported to the medical examiner's office in Charleston, W.Va.

Mr. Pile said the victim, while part of a team of miners, was working alone at the time of the accident, which would not have been unusual. Mr. Pile did not know how deep in the mine the accident occurred.

State mining officials and representatives of the federal Mine Safety and Health Administration were at the scene Friday evening and yesterday morning. They plan to interview workers about the accident tomorrow.

Caryn Gresham, a spokeswoman with the West Virginia Office of Miners' Health, Safety and Training in Charleston, yesterday said, "Our investigator, the inspector, told me that it was a rib roll."

A rib roll, according to a representative of the National Institute for Occupational Safety and Health in Pittsburgh, is an incident in which the side walls of a coal mine -- called the ribs -- crack and collapse into the tunnel. The rock layers that make up the roof and the floor of the mine, however, remain intact.

Ms. Gresham said the mine walls "are checked on a regular basis to make sure that their foundations are good, but I couldn't tell you how often [a collapse] occurs."

Rib rolls are relatively common, but miners are rarely hurt by them. Officials say there are one or two rib roll fatalities across the country each year.

Injuries, which number about 150 a year, occur when the coal unpredictably falling from the wall is in an unusually heavy amount and a miner happens to be in the wrong place at the wrong time.

Friday's incident was the 41st mine fatality in the United States this year, 21 of which have occurred in West Virginia. That's the most fatalities in West Virginia since 1991, when 22 coal miners were killed.

Twelve miners died after a methane explosion in the Sago Mine in Upshur County, W.Va., in January.