The most prominent is the pending trial of Bo Xilai, a once up-and-comer in the party indicted for bribery, corruption and abuse of power, China's state-run Xinhua News Agency reported Monday.
Bo, 64, a former commerce minister and municipal party leader, is accused of taking bribes of more than $3.5 million and of embezzling $800,000 from a Dalian government construction agency.
Party officials also noted four court officials in Shanghai were suspended last week and were being investigated for allegedly hiring prostitutes at a nightclub.
Last month, a township-level party official in Hebei province was fired after an investigation revealed he spent about $32,400 on his daughter's wedding banquet, which was determined unacceptable under China's anti-extravagance campaign, Xinhua said.
Investigations were conducted against several high-level CPC leaders, including Liu Zhijun, former railways minister; Liu Tienan, former vice minister in charge of the National Development and Reform Commission; and Li Chuncheng, former deputy chief of the CPC's provincial committee of Sichuan, Xinhua said. The investigation into Liu Zhijun netted a suspended death sentence.
Xinhua did not reveal the nature of the investigations against the party officials.
Party officials also investigated online accusations and charged several officials based on evidence turned up in the probes.