Five former officials in charge of environmental protection and workplace safety in east China are facing charges of graft and neglect of duty over a toxic spill caused by a copper mine killing thousands of fish last year, local authorities said Monday.

The officials were immediately investigated in the wake of the major pollution spill last July when 9,100 cubic meters of acidic waste water spewed from a poorly-built copper mine's sewage tank and polluted a river that runs through the county of Shanghang, east Fujian Province, a spokesman with the Provincial People's Procuratorate said.

Chen Jun'an, former director of Shanghang's environmental protection bureau and his deputy Lan Yong were charged with neglect of duty, corruption, and bribery in April by a local procuratorate. Chen was also accused of stealing and illegally dividing state assets, the spokesman said.

Two officials with the pollution monitoring station in Shanghang were sentenced to 21 to 27 months in prison for neglecting the duty of supervision, the spokesman added. The prosecutors are still preparing the charges for Chen Zhengping, former head of Shanghang's work safety bureau.

Last month, Zijin Mining Group Co., the operator of Zijinshan Copper Mine and its sewage facility, was ordered by a local court to pay 30 million yuan (4.6 million U.S. dollars) in damages. Five of the company's staff were jailed for three to three and a half years.

Zijin is China's leading gold producer. Operations at the Zijinshan mine were suspended after the toxic spill.