Briton in China mystery 'killed by drop of cyanide'

Extraordinary, and quite possibly officially sanctioned allegations were made last night that Neil Heywood, the Old Harrovian businessman found dead in a Chinese hotel room last November, died from poisoning by a drop of potassium cyanide.

The claim came via Mandarin language websites, one of which said that Heywood was murdered on the orders of Bo Xilai, a candidate for China's nine-man ruling elite who was until last month boss of the megacity of Chongqing. Even more remarkable, one of the sites said that the motive was jealousy and pride, claiming that Heywood had been having an affair with Bo's wife, Gu Kailai. Others favoured the idea that corruption was at the heart of the matter, claiming Heywood had helped Madam Gu spirit out of the country nearly £800m of assets. Last week, Gu was arrested for Mr Heywood's murder and Bo stripped of all his titles. He is being held under effective house arrest.

A city official has allegedly confessed that he prepared the poison – one 50th of a teaspoon is sufficient to kill – and handed it to an employee of Bo, who administered it on the party chief's instructions.

The Heywood family were told he had died of a heart attack, and Madam Gu is said to have met Mr Heywood's wife and persuaded her to request a speedy cremation. This was duly done.

These fresh claims were available on several Chinese websites last night, implying that Beijing officials were content to see them put into circulation. This is significant, but still does not prove that they are true.