A prominent Sunni Arab tribal leader who provided fighters to help battle Al Qaeda in western Iraq was assassinated Sunday in Baghdad, police said.

Sheik Osama al-Jadaan died in a hail of bullets as he was driving in the city's Mansour district, according to police Lt. Maitham Abdul Razzaq. Al-Jadaan's driver and one of his bodyguards were also killed, Razzaq said.

Al-Jadaan, a leader of the Karabila tribe, announced an agreement with the U.S.-backed Iraqi government to help with security forces track down Al Qaeda members and foreign fighters along the border with Syria, where his followers lived.

U.S. troops used al-Jadaan's followers to help find insurgents living under the protection of a rival tribe in Qaim and a cluster of nearby towns which U.S. officials said were used as a staging area for smuggling weapons, ammunition and fighters into Iraq.