British officials have revealed that evidence amassed by Scotland Yard detectives points towards Al-Qaeda militants being responsible for the assassination of Benazir Bhutto.

Five experts in video evidence and forensic science have been in Pakistan for 10 days since President Pervez Musharraf took up an offer from Gordon Brown for British help in the investigation of the December 27 killing. Last week they were joined by three specialists in explosives.

Bhutto’s widower, Asif Ali Zardari, has rejected the Scotland Yard inquiry and demanded a wider-ranging United Nations-led investigation that would also look into the bombing of Bhutto’s bus in Karachi in October.

“She was a world leader,” he said. “We don’t just want a sergeant from Scotland Yard determining the angle of fire. She’s dead - that’s the proof. We have the footage, we have the doctors who were trying to rescue her.”