Five people were confirmed dead and one is missing after a chemical plant blast in northwest China"s Gansu Province, Xinhua quoted a police spokesman as saying. "Five bodies were recovered from the scene and we found one more worker missing after checking against the name list," said Wang Xinjian, of Lanzhou Municipal Public Security Bureau. One person who was seriously injured and five with minor injuries were being treated in hospital. Nine more people were kept in hospital for observation, said Wang. The fire was under control, Wang said. The blast occurred Thursday afternoon at the plant run by the Lanzhou Chemical Company of the China National Petroleum Corporation (CNPC) near the provincial capital of Lanzhou. The dead and injured were all CNPC employees. An initial investigation showed a gas leak was the cause of the blast. Police are investigating the incident. The plant was 30 km from downtown Lanzhou. Residential buildings near the plant were not affected, officials said.