The United Nations is to begin an inquiry on Wednesday into the assassination of former Pakistani Prime Minister Benazir Bhutto as she was leaving an election rally.
The assassination on 27 December, 2007, caused turmoil within Pakistan.
The Pakistan People's Party rode a wave of sympathy to win the election, which was delayed until February 2008. Mrs Bhutto's widower, Asif Ali Zardari, later become president.
The three-member UN team is headed by Chile's UN Ambassador Heraldo Munoz. Its investigation will take six months.
The team is not empowered to begin criminal proceedings related to the assassination.
The previous government, led by Pervez Musharraf, accused a Taliban chieftain, Baitullah Mehsud, for the killing. Twenty other people died in the incident.
Interior Minister Rehman Malik believes it was an attempt to begin splitting up the country and "Balkan-ise" Pakistan.
The government recently ordered an offensive against Mehsud, who is based in South Waziristan on the Afghan border. There is a US reward of $US5 million and a Pakistani reward of 50 million rupees ($US615,000) on his head.