At least 17 miners remain trapped after a coal mine gas blast in China's Xinjiang on Saturday.
Rescuers are pouring nitrogen into the mine to dilute the gas concentration.
The process, which was started early on Sunday, needs to be continued for 24 hours before it is safe to enter the pit, China's News Agency (Xinhua) reported.
The blast happened when 20 people were working inside the mine.
Three of them have been rescued.
The company is owned by the sixth agriculture division of the Xinjiang Construction Corps, a paramilitary organization.