BEIJING: Twenty-five miners were killed and 20 trapped by a gas explosion at a coal mine in southwest China on Saturday, state media reported.

The accident occurred at 11:00 am (0300 GMT) when 131 miners were working underground at the Tonghua Coal Mine in Anwen town, Chongqing municipality, but 86 escaped, Xinhua news agency said, citing local officials.

Rescuers had recovered 25 bodies but had not yet been able to reach the 20 trapped miners due to the dangerous levels of gas, it said.

The cause of the accident was being investigated.

China's coal mines are notoriously dangerous. Official figures show that more than 3,200 workers died in collieries last year, but independent observers say the actual figure could be much higher, as many accidents are covered up.