A Chinese coal mine gas leak has killed 17 people, the latest in an all-too-familiar series of fatal accidents, just as state media trumpeted government officials pulling out their investment in the industry.

The accident happened on Monday in the city of Xinzhou in northern Shanxi province, killing 13 miners working underground.

"The management immediately sent a team of six rescuers down the pit, but two of them suffocated," Xinhua news agency said.

Two other miners in a neighbouring pit were also killed, it added.

The Fenhemao Coal Mine's business certificate and production permit had both expired, Xinha said, quoting officials with the Shanxi provincial coal mine safety supervision bureau.

State media said government officials had divested more than $50 million of interest in coal mines as Beijing [Images] steps up efforts to prevent collusion between officials and owners in the world's most dangerous mining industry, which kills about 6,000 people a year.

Of the 653 million yuan ($80.8 million) reported invested by 4,578 officials in coal mines as of October 20, 473 million yuan had been withdrawn, Vice Minister of Supervision Chen Changzhi was quoted in the official China Daily as saying.

Punishment would be reserved only for officials who invested money generated via "illegal channels" or bribery, the newspaper added.

"Investigations showed that a large number of coal mine accidents occurred because unlawful and unsafe coal mines were given a green light to operate by local governments after officials obtained stakes in the coal mines," Xinhua said.

The government has been sacking increasing numbers of local Chinese leaders for negligence in coal mining accidents, part of a larger campaign to increase checks and balances on officials' power and curb corruption, a major source of popular discontent.

In October police arrested the vice mayor of a city in northwest China on charges of complicity with a coal mine where a gas blast killed 83 people in July.

Coal accounts for about three-quarters of China's energy and the industry has strained to keep pace with voracious demand from a rapidly growing economy, the world's seventh largest.