SHANGHAI, Mar 22 -- RESCUERS have found 13 bodies in a mine after a gas blast on Sunday in a search operation delayed for two days because of a coverup, said work safety officials in north China's Shanxi Province.

In a separate case, officers in Liaoning Province, northeast China, yesterday detained a mine owner accused of trying to conceal a fire that killed six miners.

The Shanxi mine blast occurred at the Miaojiang Coal Mine, in Chengqu District of Jincheng City. The mine owner is suspected of failing to report the accident to the emergency services, said sources with Shanxi Provincial Bureau of Work Safety.

On Tuesday afternoon, people close to the company reported the accident to the provincial bureau of work safety, which ordered Jincheng City Bureau of Work Safety to immediately investigate.

A team from the bureau on Tuesday confirmed the explosion. A rescue team arrived at the site late Tuesday to discover the main shaft and the side passage were sealed off.

The rescuers unblocked the shaft and found the miners had been working beyond the officially approved coal bed.

Police have detained 11 people in connection with the coal mine gas explosion, including Wang Junjun, the owner of the Miaojiang Coal Mine.

The Shanxi Office for Resources Integration had instructed the Miaojiang mine to merge with the nearby Gaojiang Coal Mine, with a combined production limit of 90,000 tons a year.

Instead of following the instruction, the operators of the Miaojiang mine organized production illegally and breached the approved stratum for coal mining, which led to the accident, said a spokesman for Jincheng City government.

All coal mines in Jincheng, in the southeast of Shanxi, had been ordered to stop production to carry out safety evaluations since the blast.

In the suspected fire coverup, police yesterday arrested Xiang Fangshu, owner of the coal mine in Dongliang Township of the Mongolian Autonomous County of Fuxin.

A flooding on March 10 at another coal mine in the province killed 23 workers.

(Xinhua)