All the 20 miners who were trapped in a flooded coal mine for more than 30 hours in north China's Shanxi Province have been evacuated from the shaft safely at around 5:56 p.m. Friday and sent to hospitals for treatment, the local rescue headquarters said.

The accident took place at around 11 p.m. Wednesday at the coal mine in Duxigou Village, Xiaoyi City. Illegal mining was blamed for the accident, according to a preliminary investigation.

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Rescuers on Friday morning established contact with the miners. The first trapped miner was lifted out of the shaft at around 2:15 p.m. Friday.

More than 400 rescuers had been racing against time to reach the trapped miners. Several pumps had been installed, and the water level in the pit had dropped by 2.1 meters as of 6 a.m. Friday, rescuers said. Low temperatures and strong winds were making search and rescue more difficult.

The local public security department has put under control seven suspects involved and is searching for others who have fled.