Six Americans and three Bulgarians were among 11 people killed when a commercial helicopter was shot down north of Baghdad Thursday.
Bulgaria's Defense Ministry says missile fire was responsible for the crash of the Mi-8 helicopter, which is owned by a Bulgarian company.
Officials originally put the death toll at nine but raised it to include two guards from an unspecified country who were killed in the crash.
The U.S. military had contracted the aircraft through the Canadian company SkyLink to transport workers of an American firm, Blackwater Security.
In a separate incident Wednesday, two people were killed when a bomb blast hit a convoy carrying foreign contractors on the road to Baghdad's airport.
Meanwhile, al-Qaida in Iraq claimed responsibility for an assassination attempt on Iraqi interim Prime Minister Iyad Allawi. Mr. Allawi escaped harm when a car bomb exploded near his motorcade in Baghdad late Wednesday.
The violence raged on as Sunni, Shi'ite and Kurdish politicans continue negotiations over a new Iraqi cabinet.