Four miners were killed after the roof of a mine in southwest China's Guizhou province collapsed on Wednesday, local authorities said Thursday.

There were 35 miners on duty at the Yebiao Coal Mine, located in the town of Pingzheng in Zunyi county, when the accident happened.

Thirty-one miners managed to escape, while the remaining four became trapped underground, according to the provincial work safety bureau.

One miner died at the scene, while the other three died at a local hospital after being pulled from the mine, the bureau said.

The cause of the accident is under investigation.