Delay in critical Pakistani election expected

But a spokesman for Mehsud, Maulana Mohammed Umer, dismissed the allegations as "government propaganda."

Bhutto's aides said they, too, doubted Mehsud was involved and accused the government of a cover-up.

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"The story that al-Qaida or Baitullah Mehsud did it appears to us to be a planted story, an incorrect story, because they want to divert the attention," said Farhatullah Babar, a spokesman for Bhutto's party.

Authorities initially said Bhutto died from bullet wounds. A surgeon who treated her later said the impact from shrapnel on her skull killed her.

But Cheema said Friday that Bhutto was killed when the shock waves from the bomb smashed her head into the sunroof as she tried to duck back inside the vehicle.

Bhutto's spokeswoman Sherry Rehman, who was in the vehicle that rushed her boss to the hospital, disputed that.

"She was bleeding profusely, as she had received a bullet wound in her neck. My car was full of blood. Three doctors at the hospital told us that she had received bullet wounds. I was among the people who gave her a final bath. We saw a bullet wound in the back of her neck," she said. "What the government is saying is actually dangerous and nonsensical. They are pouring salt on our wounds. There are no findings, they are just lying."

Cheema stood by the government's version of events, and said Bhutto's party was free to exhume her body for an autopsy.

The election commission has called an emergency meeting for Monday to decide how to proceed with the parliamentary elections.

Riots have destroyed nine election offices — along with the voter rolls and ballot boxes inside, the election commission said.

In the eastern city of Bahawalnagar, meanwhile, two suspected suicide bombers died early Sunday when they prematurely detonated their bomb near the residence of Ijazul Haq, a senior leader of the Pakistan Muslim League-Q party, police said. Haq was not at home at the time. The blast was the first suicide attack in Pakistan since Bhutto's assassination.

Reuters and The Associated Press contributed to this report.

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