No part of China's ruling Communist Party is off limits for its crackdown on corruption, the top graft-buster was quoted as saying, sounding a warning a few days after one of the country's most senior former soldiers was purged.

The party announced last week that Xu Caihou, who retired last year as vice-chairman of the Central Military Commission, had been expelled and will be court-martialled after being accused of corruption.

Wang Qishan, who heads the party's efforts to combat corruption, warned that every part of the party would be liable for inspection.