Six people are dead and another is injured in a cave-in caused by a tremor at a colliery in northeast China, the local authorities confirmed on Thursday.

The tremor occurred around 9:20 a.m. on Wednesday in the Hengda coal mine in Fuxin City, Liaoning Province. It caused the collapse of a 20-meter section of a tunnel, trapping seven people working at the site, according to the provincial coal industry administration.

Rescuers recovered the bodies of two miners at 2 p.m. on Wednesday. They established contact with four trapped miners at 4:30 p.m. and rescued three of them at 8 p.m..

The three miners, who were still able to speak when they were brought out of the pit, were taken to hospital immediately.

Rescuers found the last two trapped miners alive at midnight after they had been buried for 14 hours.

Four of the five miners had died by 6 p.m. on Thursday, despite medical treatment. One was still alive and out of danger, doctors said.

The provincial authorities, including the work safety bureau and the department of labor and social security, have launched a joint investigation into the cause of the accident.

The local seismological station put the tremor's magnitude at 1.7 on the Richter scale.

The mine belongs to the Fuxin Mining Industry (Group) Co. Ltd. The cause of the tremor remains unclear.

(Xinhua News Agency August 1, 2008)