AN underground explosion has reportedly killed 30 miners and injured 77 at the Tonghua colliery in Qijang county, southwest China, on the weekend.

Xinhua has reported State Administration of Coal Mine Safety head Zhao Tiechui as saying the excessive use of explosives and poor evacuation procedures led to the death toll from the accident on Saturday.

Zhao told the state-owned news service the mine’s owners had emphasised construction over safety, and management had not evacuated workers before a planned detonation.

China Daily reported the mine owner, project manager and chief engineer have been detained, and two managers have been relieved from their positions.

The miners were reportedly about 1000m underground and 101 had to be rescued.

Three of the injured workers remain in a critical condition.

The biggest accident to the nation’s coal industry so far this year was the underground explosion at the Tunlan Colliery in northern Shanxi Province, which killed 78 people and injured 114 in February.