BEIJING, Sept 12, 2007 (AFP) - The mistress of a former high-ranking official in eastern China was on Wednesday charged with corruption in one of the first prosecutions under tougher anti-graft rules, state media reported.

Wang Peiying, the long-time mistress of the former transport chief of Zhejiang province, was charged with taking bribes worth 550,000 yuan (73,00 dollars) from a construction company, the Xinhua news agency reported.

Wang then helped the company beat 70 other bidders to win a contract to build a new terminal at a local airport in 1998, while her lover, Zhao Zhanqi, was in charge of the construction project.

Zhao, now 58, was sentenced to life in prison in July for receiving 6.2 million yuan in bribes from 1994 to 2006.

Xinhua said Wang was charged by a local court under tightened anti-graft rules issued in July that clarified the illegality of "new forms" of bribery, including profits gained through close relatives and lovers.

"Chinese prosecutors have long been wise to the fact that the identification of a mistress usually means a significant breakthrough in a corruption investigation," Xinhua said.

"However (until the toughened laws were introduced) it had been hard to link the suspects with their lovers' actions in court."