Yixing city prosecutors in east China's Jiangsu Province have charged Wu Lihong, who was once nominated as one of China's top ten environmentalists, with blackmail, sources with the local people's procuratorate said Wednesday.

Arrested in April, Wu was alleged to have extorted 55,000 yuan (about 6,875 U.S. dollars) from enterprises by threatening to expose how they were polluting the environment, according to the prosecutors.

The Yixing people's court has yet to set a date for the trial.

Prosecutors said Wu's diary detailed a list of blackmail targets and showed amounts of money he had planed to extort from each factory or enterprise involved in pollution.

Wu led a campaign to clean up the Taihu Lake, which is now so polluted that water supplies had to be cut to two million people in Wuxi city in late May.

Wu was hailed as an eco-warrior for spending years and all his money to expose and report on contaminating factories. The provincial environmental administration of Jiangsu recommended Wu for national honors for his advocacy work in 2005.

"If I become one of the 'Top Ten Environmentalists', it proves that my long-time environmental efforts have been worthwhile," said Wu at the time of his nomination.

Zhang Lijun, vice head of the State Environment Protection Administration (SEPA), said on Tuesday that Wu was reported to be involved in illegal activities but added that "environmental protection departments always regard environment advocates as allies."

Source: Xinhua