According to a preliminary report provided to ILN Monday afternoon, two unnamed miners at Massey’s Mammoth Coal Alloy Powellton operation were injured at the No. 1 section just after midnight on February 10.

“The miners were standing beside a roof bolting machine that was bolting #7 face when a rib measuring 8 feet, 10 inches high containing a gray shale layer at the top measuring 72 inches long, up to 23 inches high and 11-18 inches thick collapsed, striking the miners,” the documentation confirmed.

One worker suffered potential ligament damage to the right knee, while the other received a fractured sternum.

Updates on the conditions of both workers were not available from state or federal officials Monday afternoon. An ILN request for further details or updates from Massey was not immediately returned.

State and federal investigations into the incident have begun.

According to Mine Safety and Health Administration data, a total of 74 employees work at the mine with 70 underground. It was not confirmed how many individuals were working underground at the time of the rib roll.