Seven people were injured in a chemical plant fire in east China's Zhejiang Province, local news sources said Monday. The fire engulfed a three-story New Oriental chemical plant in the province's city of Taizhou at approximately 3:05 a.m. after an explosion took place inside the plant, Xinhua reported. Seven people were injured, with four in serious condition. They are now being treated at a local hospital. The fire was put out two hours later and the cause of the explosion is under investigation.