A couple papers said there were bombers.
Here are two...
Benazir Bhutto assassinated at election rally
Submitted by Tarique on Thu, 12/27/2007 - 14:35. Muslim World News Crime/Terrorism
By IANS
Islamabad : Former Pakistan prime minister Benazir Bhutto died a gory death Thursday when a suicide bomber blew up at an election rally and a gunman then fired at her even as she lay bleeding.
Bhutto, 54, who returned to her country only two months ago after eight years in exile, was injured when the attack took place at a Pakistan Peoples Party (PPP) meeting at Liaqat Bagh in Rawalpindi, near here.As panic swept the venue, with bodies strewn all around, a motorcycle rider sped past firing away, apparently pumping bullets at her neck, witnesses and party officials said.A profusely bleeding Bhutto was rushed to a hospital but she died, PPP official Rehman Malik said.
http://www.indianmuslims.info/news/2007/dec/27/benazir_bhutto_assassinated_election_rally.htmlPakistan on the Brink: Assassination of Benezir Bhutto triggers widespread violence in Pakistan
By Animesh Roul
Pakistani opposition leader Benazir Bhutto was assassinated in a terror attack during a political rally in the garrison city of Rawalpindi. Over 20 people killed and many more injured in this suicide attack. As per sources, the Pakistan People's Party (PPP) leader was shot in the neck and chest as she was entering her vehicle after addressing the campaign rally at Liaqat Bagh Park. (This where Pakistan's first prime minister Liaqat Ali Khan was assassinated in early 1950s).
Soon after the gunshot, the bomber blew himself up amid the crowd. It was reported that the bombers came in a motor bike. Another version coming from the government sources that she died when splinters/pellets from the blast pierced in her body. http://counterterrorismblog.org/2007/12/pakistan_on_the_brink_assassin.php