The Iraqi government has assumed command of U.S.-backed Sunni Arab militia groups that have been fighting al-Qaida insurgents.
As of Wednesday, members of "Awakening Councils," also called "Sons of Iraq," will receive their salaries from the Iraqi government, not the U.S. military. It is seen as a key test of reconciliation between Iraq's two main religious sects.
Many of the 100,000 "Sons of Iraq" are former insurgents. Their help in battling al-Qaida in Iraq members has contributed to the fall in violence across the country. But many of the Sunni members fear that the Shi'ite-led government will arrest and possibly kill them.
A Pentagon study released Tuesday expressed concern that the integration is happening too slowly and could rekindle violence if it fails.
About 20 percent of the fighters are expected to be integrated into Iraq's security forces, while the rest will take other government jobs.
In a separate development, Iraqi officials say 359 civilians were killed in the country in September. That is 23 fewer civilians than were killed in August.
Some information for this report was provided by AFP and Reuters.