Four miners were killed and another 11 possibly suffocated to death from methane gas in a coal mine in Southwest China's Guizhou Province.

"Hope remains dim" that the 11 miners have survived the disaster that happened on Sunday evening in Wulunshan Coal Mine in the province's Nayong County, a coal mine head said.

"Thick gas underground has stopped our rescue efforts and the 11 miners are possibly dead," he told China Daily yesterday via phone, refusing to be named.

Eighty of the 104 miners working underground when the accident occurred were lifted out to safety. One miner was already dead, nine were injured and 14 were trapped underground on Sunday evening.

Another three miners were found dead underground by the rescue team yesterday. "The team cannot reach the remaining miners because the density of methane gas is too high," said the mine spokesman.

The Wulunshan mine is a State-owned enterprise, which began operation last year. Information from the State Administration of Work Safety revealed the mine was in the process of applying for a safety licence, which means it was operating illegally.

Wang Xianzheng, vice-minister of the national safety watchdog recently warned that Guizhou, a province producing 5 per cent of China's total coal, was facing a huge challenge in work safety, as nearly one-seventh of the annual death toll from the country's coal pits belonged to the mountainous province.

Source: China Daily