KUNMING - Three people have died and another is missing after a roof of a coal mine where they were working collapsed in Southwest China's Yunnan province Wednesday, local government officials said.

The accident occurred around 1:30 pm at the Shuimichong Coal Mine in Qiubei county of Wenshan Zhuang and Miao autonomous prefecture.

Of the four miners buried underground, three have been confirmed dead while rescuers are still searching for remaining one, officials with the prefecture's government said.

The mine, with an annual producing capacity of 40,000 tons, is licensed.

The cause of the accident is under investigation.