Dozens of people have been reported dead in separate mining accidents in central and north-west China.
At least 13 miners have been trapped underground in a coal shaft when water gushed into the mine in north-western China on 18 July.
In another major accident, 28 miners were killed on 17 July when an electrical cable caught fire inside a coal shaft of a mine owned by Xinxin Mining in northern Shaanxi province.
A primary police investigation found the mine's licence expired in early June and that it was operating illegally.
In a third mining accident, eight miners died when a coal mine operated by the Zhengzhou Coal Industry Group caught fire in central Henan province on 17 July.
China's coal industry has the highest number of mining accidents in the world with 2,600 deaths in 2009.