Eight miners have been rescued and 21 remain trapped in a coal mine that flooded in northwest China’s Xinjiang region, Chinese state news agency Xinhua reported on Sunday, citing a local emergency department.

A part of the mine flooded leading to power outages just after 6 p.m. (1000 GMT) on Saturday when 29 miners were working at the mine located in Xinjiang’s Hutubi county, the report said.

In a separate report, state media outlet Global Times said 12 of the miners who remain trapped have been located in the mine as of Sunday and are expected to be rescued, while a further nine workers have not been located.

Chinese mines are among the deadliest in the world.

Ten gold miners were confirmed dead in January following an explosion in a mine in China’s coastal Shandong province.

In December, 23 people were killed after being trapped in a mine in the southwestern city of Chongqing. Three months earlier, 16 people died in a separate coal mine in the same area.

State media on Sunday said rescue efforts in the Xinjiang mine were ongoing.