Wu Bing, tycoon with Hong Kong ties, believed to be in detention

Tycoon Wu Bing, who has an intertwined relationship with the country's oil industry and Sichuan officialdom, has reportedly been detained by authorities.

Wu, who also goes by the name Li Ruochen and Wu Yongfu, is chairman of Hong Kong-registered Zhongxu Limited and the behind-the-scenes owner of various businesses, including Zhongxu Investment Corporation, a company based in Sichuan's capital, Chengdu, registration documents show.

He is believed to have been seized in Beijing on August 1, two major mainland news organisations have reported, quoting anonymous sources.

In the past few months, overseas political gossip websites have been linking the 50-year-old with former security tsar Zhou Yongkang who is under Communist Party investigation for corruption.

Wu has not been seen in public since May 22, the same day he donated HK$10 million to the government of Yaan in Sichuan province. The city was hit by a 7-magnitude earthquake in April, the official Sichuan Daily reported.

Although he is believed to be one of the richest men in Sichuan, which is Zhou's power base, Wu has shied away from the limelight.