Five people were killed and two injured in a coal mine gas outburst in southwest China's Guizhou Province early Thursday, local authorities said.

The accident occurred at about 4 am under a transportation shaft of Nengtong Coal Mine in Pu'an county of Qianxinan prefecture when nine workers were doing maintenance work, the county government said in a press release.

Of four people who managed to escape to safety, two were under medical treatment but suffered no life-threatening injuries. The rest five were killed as emergency treatment failed to save their lives.

All coal mines in Pu'an county have been ordered to suspend production for a sweeping safety inspection.

A deputy director of the county bureau of work safety and mayor and a deputy mayor of the town where the coal mine is located were suspended from their posts.

The Nengtong Coal Mine has an annual production capacity of 150,000 tonnes.