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A British businessman was murdered after he threatened to expose orders from a Chinese leader’s wife to move money abroad, sources close to a police investigation tell Reuters.

Gu Kailai, the wife of Bo Xilai -- who was hoping to expand his power in the Communist Party during a leadership transition this fall -- asked Neil Heywood to help her move a large sum of money abroad.

But after Heywood, 41, saw the size of the transaction and demanded to keep a bigger portion of cash as part of the deal, Gu became outraged. Heywood responded by threatening to expose her actions, Reuters reports.

"Heywood told her that if she thought he was being too greedy, then he didn't need to become involved and wouldn't take a penny of the money, but he also said he could also expose it," the first source told Reuters.

Heywood's body was found Nov. 15, 2011, at the mountaintop Nanshan Holiday Hotel on the southern outskirts of Chongqing, according to people briefed on the investigation.

The body was cremated without an autopsy being performed, and the hotel's remote location adds to the mystery surrounding Heywood's final hours.

The sources said police believe he died after being poisoned by a drink.

Bo and Gu are said to be under some form of detention in Beijing, but no details have been released on the state of the investigation or a possible trial. Bo has not been seen since March, after he held a news conference at Chinese parliament and blasted the “filth” being poured on his family, Reuters reports.

Gu is suspected in Heywood's murder and faces a possible death sentence. Outside of the report from the sources, no motive for the crime has been publicly released, other than the Chinese State media admitting Heywood was killed in a financial dispute, Reuters reports.

Bo was once considered a leading candidate for the party's all-powerful Politburo Standing Committee, which is expected to name seven new members at a party congress in the fall, in the first step in a generational handover of power to younger leaders.

However, his removal as Chongqing's Party Secretary on March 15 and suspension of his membership in the Politburo last week have effectively ended his political prospects.

On Monday, Chinese Premier Wen Jiabao demanded tougher anti-corruption efforts amid the huge political scandal.

Wen's message differed little from previous calls to fight endemic corruption. But it comes amid a nationwide drive to support the Communist Party's decision to oust Bo from key positions and launch an investigation into what are described as serious breaches in discipline, the Associated Press reports.

Media reports have raised questions about whether he tried to abuse his power to quash the investigation into Gu.

Wen wrote in an essay published in the party's main theoretical journal, Qiushi, that despite a series of measures enacted to curb corruption, greater determination and more effective anti-corruption tools are still needed.

Wen did not mention Bo by name or refer to the case directly. However, Wen has been the only top official to speak publicly about the matter, saying at his annual news conference last month that Chongqing officials need to understand its seriousness and put their house in order, the Associated Press reports.

Also Monday, party newspaper Guangming Daily published the latest in a series of state media editorials calling on readers to support action against Bo and his wife and not to believe speculation that the politician's sidelining is linked to infighting among top leaders.

British Prime Minister David Cameron is expected to address the murder when he meets with senior Chinese Communist Party official and Politburo member Li Changchun, on Tuesday, BBC reports.

The Associated Press contributed to this report.

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