Three miners missing after a coal mine tunnel collapsed in Luntai, a county in southern Xinjiang Uygur Autonomous Region, have been confirmed dead, bringing the death toll for the accident to seven, local sources said on Thursday.

The accident took place around 4 PM on Tuesday at Baoshan Coal Mine, some 60 km from the county seat of Luntai, while miners were working to seal off a fire. Four were killed on the spot and three went missing, said sources from the Southern Branch of Xinjiang Regional Bureau of Coal Mine Safety Supervision.

"Rescuers pinpointed the missing miners' location after the accident, but the collapse and high gas concentration greatly hampered the rescue operation," said Bian Deyun, director of the branch.

"Judging from the difficult situation down the shaft, the missing men must be dead," Bian added.

The toxic gas concentration in the shaft was well above limits and the fire got worse on Wednesday. In order to avoid injuries to rescuers, the colliery has been temporarily closed to let the fire die out.

Rescue operations will resume when the condition in the shaft permits, Bian said.

Another five injured miners have been hospitalized.

An investigation into the cause of the accident is underway.

Baoshan Coal Mine is a private coal mine capable of producing 90,000 tons of coal a year.

(Xinhua News Agency May 18, 2007)