In a number of Shiite neighborhoods across Baghdad, residents are beginning to turn away from the Mahdi Army, the Shiite militia they once saw as their only protector against Sunni militants. Now they resent it as a band of street thugs without ideology.

Blackwater USA, an American contractor that provides security to some of the top American officials in Iraq, has been banned from working in the country by the Iraqi government after a shooting that left eight Iraqis dead and involved an American diplomatic convoy.