A suspected leak of heavy metals from a mine in northern Angola is causing an “unprecedented environmental catastrophe”, affecting some two-million people in Democratic Republic of Congo, researchers at Kinshasa University said on Friday. Analysis of satellite imagery and interviews indicate a reservoir used to store mining pollutants was breached on July 15 in a diamond-mining area straddling Lunda Sul and Lunda Norte provinces in Angola, said Raphael Tshimanga, director of The Congo Basin Water Resources Research Centre (CRREBaC).