China arrests former security chief

China's powerful former security chief Zhou Yongkang has been expelled from the Communist Party and arrested, the state-run Xinhua news agency says.

Zhou became ensnared in President Xi Jinping's much-publicised anti-corruption drive in July when he was put under investigation for "serious disciplinary violation".

Xinhua said the decision to expel Zhou, 72, was made "at a meeting of the Political Bureau of the CPC Central Committee on Friday".

Zhou has also been "put under judicial probe", Xinhua added, paving the way for the prosecution of the highest ranking official since the infamous Gang of Four - a faction that included the widow of founding leader Mao Zedong.

The Gang of Four were put on trial in 1980.

Communist Party authorities have been waging an anti-graft campaign since Xi ascended to the leadership two years ago.

Zhou retired from China's all-powerful Politburo Standing Committee in 2012.