Another two Sichuan officials have been detained for criminal investigation after a chemical factory devastated the province's Tuo River with toxic chemicals. Song Shiying, vice-director of Chengdu's Qingbai river district environment office, and environmental inspection station vice-manager Zhang Ming are being investigated for dereliction of duty, Xinhua reported. The officials are the latest to be detained after the Sichuan Chemical Works Group discharged toxic chemicals into the river in February, killing up to 60 tonnes of fish, leaving nearly 1 million people without drinking water and causing up to 300 million yuan in damage. It will take as much as five years to restore the river's ecosystem. The incident triggered widespread indignation and was seen as a blatant example of local governments failing to enforce national environmental regulations. During a visit to the region in May, Vice-Premier Zeng Peiyan criticised local officials for not doing their jobs and said he felt sorry for people who were suffering because of the pollution. An initial investigation led to the sacking of the Sichuan Chemical Works Group chairman and a fine of 11 million yuan for the company. Reports have estimated economic losses from the spill at more than 200 million yuan. In addition to the criminal investigations into the two men, the report said three other local officials had been disciplined, including the director of the Qingbai river district environmental protection office, Lai Jianneng . He was fired for failing to report the spill and for not taking effective control measures, the report said. The Sichuan Environmental Protection Bureau has said the Tuo River is in grave danger because of the toxic substances discharged into it by factories. The bureau has ordered firms to cut discharges by the end of the year.