SECURITY
No one claimed responsibility for Friday's attack. But militants linked to al Qaeda, angered by Bhutto's support for Washington's war on terrorism, had earlier this week threatened to assassinate her.
Bhutto's family is no stranger to violence.
Both of her brothers died in mysterious circumstances and she says al Qaeda assassins tried to kill her several times in the 1990s. Intelligence reports have said al Qaeda, the Taliban and Pakistani jihadi groups have sent suicide bombers after her.
Bhutto has said that if she was in power she would allow U.S. forces to hit al Qaeda targets in Pakistani territory, if Pakistan's own forces were unable to carry out an attack.
Bhutto, whose first name means "unique", was born in 1953 into a wealthy landowning family. The first of four children, she was educated at a Christian mission school in Karachi, Harvard and Oxford.
The daughter of Pakistan's first popularly elected leader, her mission began in 1977 when army chief Mohammad Zia-ul-Haq overthrew her father. Twenty-one months later it became a blood feud when Zulfikar was hanged after a controversial trial.
For years Bhutto fought against Zia without success. She and her mother, Nusrat, were in and out of prison until she was allowed to go abroad for medical treatment in 1984.
In August 1988, Zia was killed in an air crash. Bhutto's election victory later that year was welcomed worldwide as the advent of democracy in Pakistan.
But many in the powerful security services distrusted her and President Ghulam Ishaq Khan sacked her after 20 months, accusing her of presiding over large-scale corruption.
She accused the establishment of rigging elections three months later to bring their protege, Nawaz Sharif, to power.
Bhutto clawed her way back in 1993 but was again kicked out of power on charges of corruption and misrule.
Asif Zardari, the businessman Bhutto wed in an arranged marriage in 1987, has been seen as her greatest liability.
He was released on bail after eight years in prison in 2004. The Oct. 5 ordinance also erased charges against him.
