Kabul, Afghanistan (CNN) -- Two Americans -- one a Green Beret -- were killed Monday when an assailant wearing an Afghan National Security Forces uniform opened fire on the group, U.S. and NATO's International Security Assistance Force officials said. The shootout in eastern Afghanistan didn't last long, as coalition forces "returned fire and killed the attacker," a U.S. official told CNN. Two Afghan army personnel also were killed, said Gen. Zahir Azimi, an Afghan Defense Ministry spokesman. A U.S. military official told CNN that at least 10 Americans were wounded as well. The assailant fired at the victims with a truck-mounted machine gun, Azimi said, after a meeting between coalition and Afghan forces at a military base in the Jalrez district of Wardak province, about an hour west of Kabul. Green Berets and Afghan forces are based there, a U.S. official said.
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A Green Beret is one of two Americans killed in Afghanistan, a U.S. official says
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Two Afghans also are killed; 10 more Americans are wounded, coalition officials say
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The assailant is dead, a U.S. official says
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It was first fatal "green-on-blue" attack on coalition troops in two months
And in the last similar fatal assault on @placeholder troops, two Americans were killed October 25.