Investigation shows that the inflow of water from nearby abandoned pits caused the flooding last Sunday of the Wutao Coal Mine in Shandan County, northwest China's Gansu Province.

The connection with the abandoned pits was made during a careless mining operation, said investigators.

More than 30,000 cubic meters of water flooded the colliery at Sunday noon, blocking 29 workers in the pit. Twelve of them survived.

Rescue work is still going on to search for the 17 trapped miners.

Ninetyfive soldiers have arrived at the mine to join the rescue efforts. At present, 500 rescuers are working day and night to save them.

Source: Xinhua