“In essence, all the evidence indicates that one suspect has fired the shots before detonating an improvised explosive device,” the report said. It said the bomber was within one or two metres of Bhutto’s vehicle with no obstruction or person in between.

Pakistan’s government has said the attack was orchestrated by a top Taliban militant commander, Baitullah Mehsud, who has links to al Qaeda. Mehsud leads Tehrik-e-Taliban Pakistan, a coalition of Islamic extremist groups fighting Pakistani forces in the lawless tribal area along the border with Afghanistan. On Wednesday, Mehsud’s coalition announced an indefinite ceasefire with Pakistani forces.

The Scotland Yard report said that despite the lack of a detailed search of the crime scene or autopsy of Bhutto’s body, “the evidence that is available is sufficient for reliable conclusions to be drawn.” Investigators relied considerably on X-rays and detailed examination of videos of the attack, it said.

The Pakistani police welcomed the findings. Senior police official Chaudhry Abdul Majeed, who is heading Pakistan’s own investigation, said they agreed with the Scotland Yard findings, adding that the attacker fired at Bhutto but missed.

Majeed confirmed that police had arrested two “important” suspects in the killing based on information from a 15-year-old boy apprehended last month in northwestern Pakistan. The boy told police he was part of a five-man suicide squad charged with assassinating Bhutto.

The two suspects, identified only as Husnain Gul and Rafaqat, appeared in court on Friday and were ordered held for 12 more days. Majeed said they appeared to have provided help to the bomber.