The attack occurred in Al-Muqdadiyah, some 100 kilometers northeast of Baghdad.
Iraq's security forces are subject to daily attack from insurgent groups.
In the northeast town of Khanaqin, near the Iranian border, police say 18 civilians were wounded in at least one explosion.
In the southern city of Samawah, fighting between security forces and alleged Shi'ite militiamen has killed at least four police officers. A curfew was in place in the city today.
(Reuters, AP, AFP)