Seven people have been killed in a colliery gas explosion in north China's Inner Mongolian Autonomous Region, local work safety watchdog said Saturday.

The blast occurred around 2:10 AM Saturday at the Liyuan Coal Mine in the Huolin Gol City in southwestern Inner Mongolia, when 23 people were working underground. Sixteen managed to escape, and seven were killed, a spokesman with the regional work safety supervision bureau said.

Local police have detained several people from the mine, and are hunting for another shareholder of mine, who absconded after the accident.

Investigators with the work safety supervision bureau said the mine was in a renovation period, and the miners should not have been operating when the accident happened.

Investigation into the cause of the accident is underway.

(Xinhua News Agency August 25, 2007)