A militant group has said it has killed 11 members of the Iraqi National Guard abducted last week and posted pictures of the killings on its website.
The Army of Ansar al-Sunna said it had beheaded one of the soldiers and shot the other ten.
Separately, a militant group is reported to have kidnapped a Polish woman who, it claims, is working for coalition forces in the country.
The Dubai-based television station, Al Jazeera, has broadcast a videotape of a woman seated between two men pointing a gun at her head.
The woman, who has not been named, demanded that Poland withdraw its forces from the country.
Poland's Defence Minister, Jerzy Szmajdzinski, has said his country will not pull its forces out of Iraq.
