CHANGCHUN, Sept. 14 (Xinhua) -- Wednesday's coal mine flooding in northeastern Jilin Province occurred after workers accidentally opened up a nearby abandoned mine tunnel, where 3,000 cubic meters of water had built up, a local government official said on Thursday.

"We often find large quantities of water in old or abandoned coal mines. The sources include rain and underground water," said Zhang Shaojiang, head of the work safety supervision administration of Tonghua City.

The accident occurred at around 5 a.m. on Wednesday at the Xiren Coal Mine in Wudaojiang town when 19 miners were working underground. Four managed to escape, the administration said.

Eight miners were rescued at 4 a.m. on Thursday and rescuers are still trying to reach the seven who are still trapped, according to Zhang.

"We are worried about the safety of the seven miners. According to the miners who were rescued, they have run into a flat tunnel which is more vulnerable to flooding," said Zhang.

Five pumps have been pumping out water since 2 p.m. on Wednesday and more than 1,200 cubic meters of water had been pumped out by 2 p.m. on Thursday.

"The water level underground is expected to become low enough at noon on Friday for the rescuers to access the tunnel," said Zhang.

With an annual production of 30,000 tons, the privately owned Xiren Coal Mine is a qualified coal mine and possesses all the required licenses for operation from the local government. No accident has ever happened at the mine before. Enditem