The Communist Party of China’s (CPC) Central Committee said on Tuesday that it was investigating Politburo member Bo Xilai over “serious discipline violations” and had suspended his membership of the powerful 25-member Political Bureau in the aftermath of a political scandal that has gripped China.

Authorities said they were also investigating Mr. Bo’s wife, Gu Kailai, in connection with the death of a British national Neil Heywood, who died in Chongqing last year following a reported business conflict with the Bo family. She is being held by judicial authorities on the suspected crime of intentional homicide.

Tuesday’s statement ended weeks of speculation over the future of one of China’s most well-known politicians and once a rising star in the CPC who was expected to play a key role in the next generation of leadership that comes to power this year. Mr. Bo’s future is in the party is now all but over while he awaits the result of an investigation by the Central Commission for Discipline Inspection.

The son of a famous founding CPC revolutionary, Bo Yibo, Mr. Bo was one of China’s most popular political figures and the darling of an increasingly influential “New Left” that saw his “Chongqing model” of welfare-focused governance and campaigns to revive Mao-inspired “Red culture” as offering much-needed solutions to China's growing problems of social inequality.

Mr. Bo, with the help of a close aide and police chief in Chongqing Wang Lijun, rose to national prominence with a corruption crackdown that brought down some 1,500 officials with mafia links in the southwestern municipality. His campaign won wide praise, but also angered many Party officials who saw the crackdown as a move by an overly ambitious politician looking to push himself into the party’s highest body, the nine-member Politburo Standing Committee.

A falling out between Mr. Bo and Mr. Wang provided the opportunity for his many detractors to bring him down. When Mr. Wang fled to a U.S. Consulate in Chengdu on February 6 seeking asylum and fearing for his life, the scandal spilled out into the public domain.

One of the reasons behind the falling out is thought to be the death of British businessman Neil Heywood in a Chongqing hotel last year. While authorities initially said he died of excessive consumption of alcohol, Mr. Wang told Mr. Bo he had evidence that the businessman, who had close ties to the Bo family, had been poisoned. Heywood had reportedly helped Mr. Bo’s son attend the elite Harrow School, and also had business dealings with Mr. Bo’s wife, Gu Kailai, who is a well-known lawyer and managed the family’s finances.

British authorities called on China to reinvestigate the case after Mr. Wang reportedly presented his evidence to officials at the U.S. Consulate. The official Xinhua news agency said in a statement that according to results of the reinvestigation, Heywood died of homicide, and Ms. Gu and Zhang Xiaojun, an “orderly” at the Bo home, were “highly suspected” and held on the crime of intentional homicide.

Beyond the scandal, Mr. Bo’s removal also exposed deeper ideological divisions within the CPC ahead of the 18th Party Congress later this year which will herald a once-in-decade transition. Mr. Bo was removed from his position as Party Secretary in Chongqing last month, one day after the closing of the parliament session during which Premier Wen Jiabao criticised Mr. Bo in a meeting with journalists, calling on him to “seriously reflect on and draw lessons” from the Wang Lijun incident. He also warned of the dangers of a return to the days of the Cultural Revolution in an apparent criticism of his neo-Maoist policies in Chongqing.

At his last public appearance during the parliament session, Mr. Bo told a small group of journalists that he believed that he was being targeted because he had taken on special interests in Chongqing and threatened entrenched power groups. “These people who have formed criminal blocs have wide social ties and the ability to shape opinion,” he said. “There are also, for example, people who have poured filth on Chongqing, and poured filth on myself and my family.”

He left with a warning, one that served as a reminder of why Mr. Bo’s populist message had struck a chord both in Chongqing and among many critics of China's development model and had catapulted him into the position of a national figure. “If only a small group of people become rich,” he said, “we will become a Capitalist society.”

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