A worker died in an industrial accident at an AK Coal Resources Inc. operation in Pennsylvania on Dec. 20, local media outlets reported.

Nevin Hostetter, 35, died of injuries sustained while operating a mobile bridge conveyor at around 3 a.m. on Dec. 20, according to Daily American, a Pennsylvania media outlet. An official with the U.S. Department of Labor confirmed that the U.S. Mine Safety and Health Administration is investigating the accident.

MSHA has recorded ten fatalities at coal mining operations so far in 2018.

AK Coal is a subsidiary of AK Steel Corp.