According to local media outlet WSAZ, the miners were working at Big River Coal’s Broad Run mine in Mason County when the car they were riding in lost its brakes and crashed into a supply car.

While none of the injuries were serious, all were taken to the hospital, WSAZ said. Four were released as of Tuesday morning.

ILN had contacted the US Mine Safety and Health Administration for comment but calls were not returned by press time. An investigation into the incident has commenced.