Seven people were killed and eight others were injured when a major fire broke out at an industrial waste treatment plant in Russia\'s oil-rich north, the emergencies ministry said on Saturday. \"Seven people died, (and) eight people received injuries,\" the regional emergencies ministry said in a statement, adding that the survivors were hospitalised. The fire broke out early Saturday at a industrial waste treatment plant located between the cities of Tyumen and Khanty-Mansiisk in the oil-rich north. Officials said earlier four people had perished in the fire, but rescue teams found more bodies as they combed through the debris of the plant, a regional emergencies ministry spokesman, Sergei Didenko, told AFP. The fire which consumed an area spanning 2,300 square metres has now been contained, the ministry said, adding that there was no threat to residential communities. Industrial accidents including fires are common in Russia and are often linked to ageing equipment and lax enforcement of safety rules.