The explosion occurred at the Huangling Mining’s No. 1 mine just before 9am on Tuesday in the country’s Shaanxi province.
Dow Jones News said 85 miners were working underground at the time of the explosion. Of them, 65 miners were rescued, including five injured miners who were rushed to hospital.
Rescue attempts are continuing to find seven miners still missing.
The mine had an annual capacity of six million tons, and begun operation in 2001.