Al-Qaeda-linked militants in Iraq have beheaded a US civilian and vowed more killings as revenge for the abuse of Iraqi prisoners, according to a film on an Islamist website.
A US State Department official said the body of an American citizen identified as Michael Berg had been found in Baghdad.
The official said Mr Berg had no ties to the US military or the defence department, but offered no further details.
Earlier, guerrillas attacked a 21-vehicle civilian supply convoy on its way to Baghdad from Jordan, and several people were unaccounted for.
Several vehicles in the convoy were destroyed in the attack close to Rutbah, near the Jordanian border.
And a bomb exploded in a crowded market in a Kurdish neighbourhood of the northern Iraq oil city of Kirkuk, killing three people and wounding around 21.
Colonel Ahmed Slamrz said the attack occurred at around 6.30am Irish time, when the market was packed with shoppers.
