Who Killed Bhutto? The Weekly Standard has this:"The Saudi royal family"

"... Musharraf was not the only party threatened by Bhutto's popularity. The Saudi royal family, who had hosted Bhutto's competitor, former prime minister Nawaz Sharif (ousted in a military coup by Musharraf in 1999), feared Bhutto would win the election. Her rise to Pakistan's highest office would weaken Saudi-Wahhabi political, economic, and religious influence in Pakistan, Afghanistan, and the rest of Central Asia. The Saudis, who loathe Bhutto, summoned Musharraf in November 2007 and talked him into allowing Sharif to return and run against her. Three days later, Sharif was on his way to Pakistan. This is an intriguing turn of events given the fact that the previous month, Musharraf had rebuffed Sharif when he had shown up in Pakistan, forcing Sharif to return to Saudi Arabia on the same plane that had brought him home..."
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