A gas explosion Tuesday in a coal mine in eastern China trapped 27 workers underground, state media reported.
Twelve other miners were lifted out of the privately owned mine in Huainan city in Anhui province after the blast, one of whom suffered burns, the official Xinhua News Agency said.
Rescuers were having difficulty reaching the trapped miners as the blast caused part of a tunnel to collapse, said Xinhua, citing Wu Zhiyong, a work safety official.
The cause of the blast was under investigation.
Xinhua said the Dongfang Coal Mine had not heeded an order from the municipal government more than a month ago for all mines to suspend production because of the flood season.
China Central Television reported that most of the trapped miners were in their 40s.
China has the world's deadliest mines, although the safety record has been improving in recent years as regulators have strengthened enforcement of safety rules.
On Thursday, a coal mine flooded in Jixi city in Heilongjiang province in China's northeast, trapping 25 workers, nine of whom were pulled out the next day. Xinhua reported Tuesday that three bodies had been found. It said 13 were still trapped and that their chances of survival were slim.