At least nine people drowned in a flooded coal mine in Shanxi's Xiangning County in an incident that was covered up by mine managers for nearly a month. The casualties did not come to light until the Shanxi Provincial Work Safety Administration received an anonymous tip-off that the Liziping Coal Mine had been flooded on July 5, Xinhua reported yesterday. Mine managers did not report the deaths to authorities, but an initial investigation by the administration revealed that at least nine colliery workers had died in the incident. A work team was set up yesterday to investigate the cover-up, the report said. In neighbouring Henan , 69 miners trapped in a flooded coal mine in Shan county since Sunday morning were safe last night, but still underground as rescuers braved heavy downpours to free them. Days of rain triggered landslides on the mountain roads leading to the Zhijian Coal Mine, which poured into the pit around 8.40am on Sunday when 102 miners were working. Thirty-three miners managed to escape, but the rest were trapped more than 1,400 metres from the entrance to the shaft and blocked by more than 600 metres of flooded tunnels, according to Zhao Shemin , a county government spokesman at the site. Mr Zhao said the miners were in a safe zone and 'emotionally stable'. 'They face no immediate danger to their lives. They have spoken with officials on the phone and know a rescue operation is ongoing. They are very stable now,' he said. Rescue operations had been complicated by the rain. 'We recorded 101mm of rain during the 12 hours before the flood. The rain did not stop until this afternoon. There was not much we could do before the rain stopped,' Mr Zhao said. He said more than 300 soldiers had been mobilised to fill cracks in a nearby river bank to ensure the water level in the shaft did not rise, and rescuers were pumping out water and drilling air holes for the miners.