Iraqi police say a suicide bomber has detonated explosives at a funeral procession, killing at least 10 people.
The attack Sunday in the town of Tikrit also injured about 20 others.
In Baghdad, some 3,700 extra U.S. troops began patrolling the streets in an effort to reduce deadly sectarian violence in the Iraqi capital.
The reinforcements were assigned to mostly Sunni neighborhoods in western Baghdad after completing a mission in northern Iraq.
Iraq has been engulfed in a wave of sectarian violence between Shi'ite and Sunni Arabs since the February bombing of a Shi'ite mosque in Samarra.
Authorities say the sectarian violence has displaced more than 180,000 people.
Some information for this report provided by Reuters and AP.
