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BEIJING, July 14 (Reuters) - Chinese authorities have begun criminal investigations into three former high-ranking officials over corruption allegations, state media said on Monday, two of whom were allies of powerful, retired domestic security chief Zhou Yongkang.
Sources have told Reuters that Zhou has been put under virtual house arrest while the ruling Communist Party investigates him for graft, though the party has made no announcement about his case.
Several of Zhou's political allies have been held in custody and questioned over corruption, including former Vice Minister of Public Security Li Dongsheng and Jiang Jiemin, who was the top regulator of state-owned enterprises for five months until last September.
The official Xinhua news agency said criminal investigations had been opened into Li and Jiang, along with another official, Wang Yongchun, who was a vice president of China's biggest oil company, China National Petroleum Corporation, the parent of PetroChina .
Xinhua provided no other details other than that all three were in custody.
As the wheels of Chinese justice can turn slowly their trials may be a long way off.
President Xi Jinping has launched a sweeping crackdown on deep-rooted graft since taking office last year, warning, like many before him, the problem was so severe it could affect the party's ability to rule. (Reporting by Ben Blanchard; Editing by Robert Birsel)