Six workers were trapped on Thursday following a rock burst at a coal mine in central China's Henan Province.

The burst happened at 11:18 a.m. when 18 miners were working in a shaft of Qianqiu Coal Mine, owned by the Henan Yima Coal Industry Group, said a group spokesman.

Twelve miners escaped, said the spokesman.

Rescue work is under way, and the cause of the accident is being investigated.