Five secretaries of the 'big Tiger'

The following five prominent officials have served consecutively as Zhou Yongkang's secretary, and most of them have been placed under investigation.

Li Hualin

, former deputy general manager of China National Petroleum Corporation, served as Zhou's secretary from 1988 to 1992. On Aug 27, the State-owned Assets Supervision and Administration Commission confirmed Li was being investigated over suspected "serious violations of discipline".

, former Party chief of CNPC International Limited, a subsidiary of CNPC, served as Zhou's secretary from 1992 to 1998. An unnamed source told Shanghai's Dongfang Daily in February that Shen had been "probed by the authorities" and had been "out of contact".

, former chairman of Sichuan's provincial federation of literary and art circles, served as Zhou's secretary from 1998 to 2003. On June 23, 2013, the CCDI announced that Guo was being investigated for suspected disciplinary violations.

, former vice-governor of Hainan province, served as Zhou's secretary from 1998 to 2008. On Feb 18, the Central Commission for Discipline Inspection of the Communist Party of China said Ji was under investigation for suspected serious violations of discipline and laws. Ji was later expelled from the CPC.

, former deputy head of the general office of the Commission for Political and Legal Affairs of the CPC Central Committee, also served as Zhou's secretary. On July 2, CCDI said Yu had been stripped of his Party membership and official post for "serious violations of discipline and law".