Six people were killed and 12 were injured in a coal mine gas outburst Sunday in southwest China's Guizhou Province, a spokesman with the provincial work safety bureau said.

The accident occurred at around 1:20 a.m. Sunday in Xinglong Coal Mine in Tongzi County, Zunyi City of Guizhou, said the spokesman.

Thirty-five people were working in the mine when the accident happened. Twenty-two people escaped, and another 12 were rescued.

One worker missing was later found dead in the mine, and five died when being taken to hospital.

Police are investigating the cause of the accident.