A gas explosion at a coal mine in northeast China early Saturday trapped 139 miners underground, state-run Xinhua news agency reported.
The incident happened at about 2:30 am (1830 GMT Friday) at a mine in Hegang City in China's Heilongjiang province, Xinhua said, quoting the provincial coal mine safety watchdog.
The watchdog said the mine is owned by the Heilongjiang Longmei Mining Holding Group.
The company confirmed that 528 miners were working in the mine when the blast occurred, of whom 389 escaped, Xinhua said, adding that rescuers were searching for the trapped miners.
An employee of the watchdog, contacted by AFP, said she was not aware of the details of the incident, adding officials were on their way to the mine.
China's coal mines are among the most dangerous in the world, with safety standards often ignored in the quest for profits and the drive to meet surging demand for coal -- the source of about 70 percent of China's energy.
Official figures show that more than 3,200 workers died in collieries last year, but independent labour groups say the actual figure could be much higher.