Pakistani police deliberately failed to properly investigate the 2007 assassination of former prime minister and opposition leader Benazir Bhutto — a political murder that could have been prevented, a UN report says.

Benazir Bhutto waves upon her return to Pakistan from exile in 2007. Her assassination shortly thereafter could have been prevented, and was improperly investigated, a UN panel says. (Lefteris Pitarakis/Associated Press)

A special United Nations commission began looking into the assassination last July as part of a deal with the Pakistani government. It delivered its conclusions Thursday afternoon.

"There was little to no focus placed on investigating those further up the hierarchy in the planning, the financing and the execution of the assassination," Chile's UN ambassador, Heraldo Munoz, who chaired the commission, said at a news conference.

Munoz also said the Pakistani government "failed in its primary responsibility to provide protection" to Bhutto on the day of her death, despite clear warnings of threats on her life.

Bhutto, whose family constituted a political dynasty in Pakistan, served as prime minister from 1988-1990 and 1993-96 before she went into exile amid corruption allegations. She returned to her homeland in October 2007 to lead the opposition Pakistan Peoples Party in a parliamentary election campaign.

On Dec. 27, 2007, Bhutto had just finished addressing thousands of supporters at a rally in the city of Rawalpindi, about 18 kilometres south of Islamabad, when a man stepped from the crowd and shot her before blowing himself up. Bhutto was hit in the neck and chest, and 23 other people died in the ensuing suicide blast.

The government at the time of Bhutto's murder, led by President Pervez Musharraf, blamed the killing on Baitullah Mehsud, a Pakistani militant commander with reported links to al-Qaeda. Officials at the U.S. Central Intelligence Agency also said Mehsud was the chief suspect.

But the Pakistan People's Party repeatedly hinted that Musharraf or his allies were involved and demanded a UN probe, asserting it was the only way the whole truth would be revealed.

Munoz on Thursday refrained from directly inculpating Musharraf, but he said a new, proper criminal investigation into Bhutto's death needs to look at not only the possible involvement of al-Qaeda, Mehsud and the Taliban but also the Pakistani establishment, including the military, intelligence agencies and the country's business elite.

"The criminal investigation of the assassination … must include a focus on those who might have been involved," Munoz said. "It should follow all leads and explore all reasonable hypotheses."

'Hindered and prejudiced'

The UN report levels 15 major criticisms at the Pakistani government's actions around the Bhutto assassination, including that the subsequent murder investigation was deliberately slipshod.

Video footage of Benazir Bhutto's last moments shows a man in a crowd aiming a gun (circled) at the Pakistani opposition leader. A suicide bomb went off seconds later. (CBC)

Pakistani officials announced just 24 hours after the killing that Mehsud was their primary suspect, "well before" it was reasonable to do so, the UN report says. This "hindered and prejudiced the subsequent investigation," Munoz said, adding that, to this day, police still have not seriously rethought whether Mehsud was involved, despite his denials.

The police probe was also marred by the involvement of the country's intelligence agencies, which meddled in crime-scene evidence gathering and drew hasty conclusions about the culprits that "pre-empted, prejudiced and hindered the subsequent investigation," Munoz said.

"The pervasive reach, control and clandestine role of intelligence agencies in Pakistani society," he continued, "has undermined the rule of law and distorted civil-military relations. At the same time it has contributed to widespread public mistrust."

The UN panel concludes that the assassination is still "shrouded in mystery and controversy" and desperately needs a fresh criminal investigation to end continuing impunity.

Police in Pakistan arrested five suspects, including a 15-year-old boy, in the months following the incident, alleging that they were part of a hit team of 12 militants. Three of the remaining conspirators are now dead, while four are at large, Pakistani officials say. Mehsud was assassinated last summer by the CIA.

In the wake of Bhutto's death, her party won parliamentary elections and eventually forced Musharraf to resign. Bhutto's widower, Asif Ali Zardari, became president in September 2008.