BREAKING: Pakistan's Bhutto Killed by Bombing

Pakistan opposition leader Benazir Bhutto was assassinated Thursday in a suicide bombing that also killed at least 20 others at a campaign rally, a party aide and a military official said.

"At 6:16 p.m. she expired," said Wasif Ali Khan, a member of Bhutto's party who was at Rawalpindi General Hospital where she was taken after the attack.

A senior military official, who spoke on condition of anonymity because he was not authorized to comment, confirmed that Bhutto had died.

Her supporters at the hospital began chanting "Dog, Musharraf, dog," referring to Pakistan's president Pervez Musharraf. Some of them smashed the glass door at the main entrance of the emergency unit, others burst into tears.