Chinese state-run media and officials praise the decision to remove Chongqing’s former Communist Party secretary, Bo Xilai, from his remaining party posts. (Feng Li/Getty Images)

The British businessman whose killing has sparked political upheaval in China was poisoned after he threatened to expose a plan by a Chinese leader’s wife to move money abroad, two sources with knowledge of the police investigation said.

It was the first time a specific motive has been revealed in the killing of Neil Heywood in November, a death that ended Chinese politician Bo Xilai’s hopes of emerging as a top central leader and threw off balance the Communist Party’s looming leadership succession.

Bo’s wife, Gu Kailai, asked Heywood late last year to move a large sum of money abroad, and she became outraged when he demanded a larger cut of the money than she had expected, the sources said.

She accused him of being greedy and made a plan to kill him after he said he could expose her dealings, one of the sources said, summarizing the police case. Both sources have spoken to investigators in Chongqing, the southwestern Chinese city where Heywood was killed and where Bo had cast himself as a crime-fighting Communist Party leader.

Gu is in police custody on suspicion of committing or arranging Heywood’s murder, though no details of the motive or the crime itself have been publicly released, other than a general comment from Chinese state media that he was killed after a financial dispute.

The sources have close ties to Chinese police and said they were given details of the investigation.

They said that Heywood, 41 — who had been a close friend of Gu and was helping her with her overseas financial dealings — was killed after he threatened to expose what she was doing.

The sources said police suspect Heywood was poisoned by a drink. They did not know precisely where he died in Chongqing. But they and other sources with access to official information say they believe Heywood was killed at a secluded hilltop retreat, the Nanshan Lijing Holiday Hotel, which is also known as the Lucky Holiday Hotel.

The sources said Gu and Heywood, who had lived in China since the early 1990s, shared a long and close relationship, but were not romantically involved.

It was not possible to get official confirmation of the case that police are building against Gu. The Chinese government did not respond to faxed questions. Some of Bo’s leftist supporters have said the case could be a campaign to discredit him.

Bo and Gu, who is in custody and facing a possible death sentence for murder, could not be reached for comment.

— Reuters