A car bomb attack today near the Afghan capital of Kabul killed two U.S. troops and four American civilian defense contractors.
The Associated Press reports the suicide attack also killed nine Afghan civilians. Two of the Afghans killed were children.
The Virginia-based contractor DynCorp International released a statement saying four of its employees working on the Combined Security Transition Command - Afghanistan program died in the attack, and three other employees were injured.
A spokesman for the Islamist group Hezb-e-Islami told Stars and Stripes it was responsible for the attack:
Hezb-e-Islami... operatives monitored NATO personnel for a week before attacking with about 650 pounds of explosives loaded in a Toyota Corolla.
The identities of the Americans killed in the attack have not yet been released.