NANJING, July 29 (Xinhua) -- The death toll from Friday's chemical plant blast in east China's Jiangsu Province has risen to22, with 28 others injured, local government sources said on Saturday afternoon.

At around 8:45 a.m. on Friday, a chemical reactor exploded upon trial run at the Fuyuan Chemical Co., Ltd. a Sino-German joint venture yet to begin production in Linhai Township of Sheyang County. The plant planned to produce fluoro benzene for industrial use.

Local workplace safety officials said 71 people were inside the chemical plant when the accident happened, and 21 of them managed to escape.

All of the injured, including the chairman, general manager and vice general manager of the chemical company, have been hospitalized, the sources added.

More than 7,000 local residents who were evacuated from the blast site have returned to their homes as local environmental protection authorities said by Friday night, the toxic gas, chlorine, from the blast had dispersed and had little influence in the air.

Preliminary investigation showed improper operation by workers was mainly to blame for the accident. Enditem