Six miners have been trapped underground after a coal mine flooding in north China's Inner Mongolia Autonomous Region Friday, local authorities said Saturday. The flooding occurred at about 4:30 p.m. Friday at the Lasengzhong Changfu Coal Mine in the Hainan District in the city of Wuhai, the general office of the Wuhai city committee of the Communist Party of China said in a statement. At the time of the flooding, eight miners were working underground and only two managed to escape, it said. Earlier rescue sources said seven were trapped. The mining accident was exposed after local police received a tip-off at about 9:20 a.m. Saturday and therefore a cover-up was suspected, it said. Local authorities have sent rescuers, policemen and medical staff to the scene following the tip-off. Currently, the rescue operation is still going on, Xinhua reported.