Eighteen people were confirmed dead after a coal shaft collapsed in northwest China, the official Xinhua news agency said on Wednesday.
At least 28 workers were working underground when the accident happened at noon on Tuesday in Shaanxi province's Shenmu county, it said.
Two of the dead had been rescued alive, but later died in hospital, the report added.
China, the world's largest producer and consumer of coal, also has the world's deadliest mining industry.
It has been battling to improve standards in its mines, but accidents are common as owners push production beyond safety limits to meet robust demand to fuel the country's economic boom.