BEIJING (AP) -- China's ruling Communist Party says a rising star once tipped for a top leadership post is under investigation.
The party said the former leader of the mega-city of Chongqing, Sun Zhengcai, is suspected of "serious violation of discipline," its shorthand for corruption and abuse of office.
No details were given in Monday's one-sentence announcement, which comes ahead of a party congress at which President Xi Jinping is expected to receive a second five-year term as party leader.
Sun sat on the party's 25-member Politburo and had been seen as a candidate for promotion to the body's Standing Committee, the select group of leaders who constitute the apex of political power in China.
He was removed suddenly from his Chongqing post last week and replaced by Xi protege Chen Min'er.