At least 21 miners have been killed and five wounded in a coal mine explosion in China’s south-western Guizhou province.

Rescue operations are continuing at the privately run Yuanyang colliery as several unaccounted miners are believed to be still trapped underground, reports official china news agency Xinhua.

A total of 31 miners were working in a shaft of Yuanyang colliery when the accident occurred due to a gas burst triggered by the detonation of explosives for illegal mining, the rescue headquarters said.

The survivors are being treated for the effects of carbon monoxide inhalation.

In March this year, about 115 miners were rescued in a massive search operation from a flooded pit in Shanxi province.

Last year 2,631 people died in 1,616 mine accidents, according to official figures.