The facility, Songzao Coal Mine, is owned by state energy firm Chongqing Energy and located just outside the city of Chongqing, AFP reported.
Mining accidents are common in China, where the industry has a poor safety record and regulations are often weakly enforced.
At least 14 miners were killed in a coal and gas blast last December at a mine in southwestern Guizhou province.
In December 2018, seven miners were killed in Chongqing after the connecting segment of a skip broke and fell down a shaft.
In October the same year, 21 miners died in eastern Shandong province after pressure inside a mine caused rocks to fracture and break, blocking the tunnel and trapping the workers. Only one miner was rescued alive.