Little hope is now held in China for 11 missing miners after a gas leak in a coalmine killed 26 others.
The missing men are considered likely to have been buried by thousands of tonnes of coal dust that smothered the pit.
The Xinhua news agency reported the explosion happened early on Saturday at the Yuzhou pit, which is owned by Pingyu Coal & Electric Co Ltd.
The BBC reports that China's mining industry is the most dangerous in the world - more than 2600 miners were killed in accidents in 2009.
The government has closed more than 1000 illegal pits this year.