In a village just north of Baghdad, a car bomb killed three police officers and wounded nine others.
In the south of the capital, a roadside bomb hit a vehicle carrying Sahwa militiamen fighting al-Qaeda, killing two and injuring two others. Another blast targeted an army patrol killing one Iraqi soldier and wounding two others, reports said.
No-one has said they carried out the bombings.
Violence in Iraq this year has reached a level not seen since 2008.
The UN has said the monthly death toll dropped to 659 in November, including 565 civilians and 94 members of the Iraqi security forces, compared with 979 in October.