Zhou Bin, the younger son of former top security chief Zhou Yongkang, has been placed under detention on a charge of illegal business dealings, an article on Caijing magazine's website said on Tuesday.

Top officials probed since 1978

Zhou's associates under probe

The article said Zhou Bin's case signals that China's anti-corruption campaign has entered a new phase.

Zhou Bin was born in January 1972 when his father worked on the Liaohe oilfield, the article said, citing an unnamed source close to the matter.

The source said Zhou Bin started in business after studying abroad, adding that he ran his business cautiously and hired lawyers during the early stages of his career to avoid any risks.

With Zhou Yongkang's success in officialdom, Zhou Bin’s business expanded from Beijing to Sichuan and overseas and was worth hundreds of millions of yuan, the article said.

Zhou Bin's wife and mother-in-law held positions in his companies and are shareholders.

Zhou Bin's cousin Zhou Feng, also a business magnate, ran businesses in the Xinjiang Uygur autonomous region, the Inner Mongolia autonomous region, Tianjin and Jiangsu province.

Zhou Feng and his father, Zhou Yongkang's brother, as well as their relatives, were placed under detention in 2013 for investigation.