A top Chinese official in Beijing's secretive Rocket Force has been placed under investigation for corruption, state media said, deepening a crackdown on alleged graft in the military.

Sun Jinming was kicked out of the ruling Communist Party and is under investigation for "grave violations of party discipline and laws", state news agency Xinhua said Thursday, using a common euphemism for graft.

The news came in a communique issued to mark the end of the Communist Party's Third Plenum, which began Monday and ended Thursday.

Beijing also confirmed Thursday that PLA ex-Rocket Force commander Li Yuchao had been expelled from the party and stood accused of "grave violations of discipline".

Thursday's readout marked the first time that the investigation into Sun, appointed chief of staff of the People's Liberation Army (PLA) Rocket Force in 2022, had been made public.

Chinese President Xi Jinping has launched an aggressive, wide-ranging anti-graft campaign since coming to power.

In the past year that campaign has turned its attention to the secretive Rocket Force, the army unit that oversees Beijing's nuclear arsenal.

Its head, Li Yuchao, was replaced last July.

And Li Shangfu was ousted last year after only seven months as defence minister following a lengthy absence from public view.

He was later expelled from the Communist Party for causing "great damage to (its) cause" through offences including suspected bribery.

Other disgraced generals include Wei Fenghe, who once headed the Rocket Force and who later became China's defence minister from 2018 to 2023.

State broadcaster CCTV said in June that Wei had been expelled from the ruling party and passed on to prosecutors over alleged corruption.

The Rocket Force is a relatively new unit of the Chinese military.

Its creation was announced after a major reorganisation of China's military structure.

It oversees China's arsenal of strategic missiles, both conventional and nuclear, and can both deter and strike, according to the government.