British businessman Neil Heywood was poisoned with cyanide after siphoning nearly $1.3 billion out of the country for Bo Xilai (薄熙来) and wife Gu Kailai (谷开来).
Bo and his aides are said to be behind the killing because Heywood was having an affair with Gu.
Heywood was found dead in a Chongqing hotel. It was said at the time that he drunk himself to death, and he was quickly cremated.
But now a Chongqing official has admitted preparing the poison on the orders of Bo.
Bo has since been purged from the Communist Party politburo and is under house arrest, along with his wife.