(KABUL, Afghanistan) -- The latest spate of "green on blue" shootings in Afghanistan has cost the lives of three more American soldiers.
NATO said on Friday that the troops were killed late Thursday in the southern province of Helmand by a gunman dressed in an Afghan security forces uniform.
The assailant was identified as a police checkpost commander who managed to escape after the shooting. The shooter remains at large.
Earlier this week, two men dressed in Afghan uniforms gunned down an American soldier in eastern Afghanistan, while another uniformed attacker was shot dead Thursday when he fired on NATO troops in Laghman province.
So far in 2012, there have been more than 25 "green-on-blue" shootings in which coalition troops have died at the hands of Afghan soldiers or insurgents posing as security forces.
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