RESCUERS in southern China are trying to reach more than 40 workers in two coal mines after one pit was flooded and the other caved in, BBC reported Sunday. They are venting explosive gas and pumping water from a mine in Guangxi region, where three miners died. Flooding has continued to hamper rescue work at the other mine in the neighbouring province of Guizhou. China 's mines are the world's deadliest; more than 2,600 miners died in accidents in 2009 alone. Heavy rain was said to have caused the latest accidents.