Five people were killed in an explosion at an oil drilling plant in northwestern China, local government officials said on Monday. Five others were injured and three were missing after the blast at the Qilicun site operated by government-backed Shaanxi Yanchang Petroleum Group on Sunday evening, they said. The plant, located 40 kilometres east of Yanan city in Shaanxi province, had just started testing thermal technology to increase output. “The injured people have been taken to the hospital and their life signs are stable,” the local government statement said. “Rescue work is continuing and the reason for the accident remains under investigation.” Two killed, 12 missing after huge blast at gas plant in central China In 2017, Qilicun produced 385,500 tonnes of crude oil. It was unclear if production at the plant had been halted. Yanchang could not be reached for comment. .