An Afghan policeman conducting a joint operation with U.S. soldiers opened fire on the Americans, killing two of them before fleeing, an Afghan official said Saturday.
The U.S. military earlier said two American troops died in a firefight in Wardak on Friday, but declined to confirm any new details.
Shahidullah Shahid, a spokesman for the Wardak provincial governor, said the policeman fired on the Americans while they were patrolling together Friday night, killing two and injuring two. Shahid said two of the officer's relatives were in custody for questioning.
A third U.S. service member died Friday of wounds from a bomb attack in Wardak the day before.
Afghan forces have periodically turned their guns on international troops, most recently in August when two policemen opened fire on a joint patrol in the northeast. In that case, the policemen were shot to death and no coalition forces were reported killed.
In far western Afghanistan, a Taliban attack Saturday on a NATO supply convoy killed a civilian contractor escorting the trucks, said Raouf Ahmadi, a regional police spokesman.
In the north, a Finnish convoy hit a roadside bomb, destroying one of the vehicles and injuring four soldiers, Afghan and Finnish officials said. Northern Balkh province, where the Finnish soldiers are based, has been relatively peaceful but still sees some violence.
U.S. and NATO deaths dropped in September over the previous two months — possibly due to the Muslim holy month of Ramadan or because no major offensives were launched. But since President Barack Obama's decision to send 21,000 more troops to curb the growing Taliban-led insurgency, international and civilian tolls have risen steadily.
U.S. forces mounted major operations in July and August in southern Afghanistan to try to dislodge the Taliban from longtime strongholds and improve security ahead of the Aug. 20 presidential election, the outcome of which remains in doubt because of allegations of massive fraud by supporters of President Hamid Karzai.
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