The US defence secretary, Leon Panetta, has confirmed that a doctor now in prison in Pakistan was working with the US Central Intelligence Agency on a fake vaccination campaign to help track down the whereabouts of Osama bin Laden.

Shikal Afridi had claimed to be running a hepatitis B vaccination campaign as a ruse to gain entry to the compound in Abbotabad where bin Laden was living. The aim was to obtain DNA samples from those inside the compound that could be matched with bin Laden family DNA already on file at the CIA.

US officials say that Dr Afridi gained access to the compound but did not see bin Laden or obtain any DNA samples. However, in an interview on CBS News, Mr Panetta, who was director of the CIA at the time, said …