Gunmen shot and killed eight members of the same family and cut the heads off some of them on Monday in a mainly Sunni Muslim district southeast of Baghdad, a senior security official said.
Beheadings are a trademark of Sunni Islamist insurgent groups such as al Qaeda.
Unknown gunmen killed eight members of the same family with silencers, and cut the heads off some of the bodies, the office of Baghdad security spokesman Major General Qassim al-Moussawi said in a statement.
The attack took place at about 7am local time (0400 GMT) in the al-Wahda neighborhood of the Madaen district outside Baghdad, the office said. No further details were given.
Violence has fallen sharply in Iraq in the last two years, but bombings and shootings are still common. Some fear more attacks in the lead up to the March 7 parliamentary election.
(Reporting by Suadad al-Salhy; Writing by Mohammed Abbas; Editing by Louise Ireland)