NATO's International Security Assistance Force (ISAF) said the soldier died during an operation and that air support was used against insurgent positions.
The nationality of the soldier was not released.
Taliban militants stepped up attacks in 2006, and insurgent-related violence killed some 4,000 people in the bloodiest year since the U.S.-led coalition ousted the Taliban in late 2001.
RFE/RL Afghanistan Report
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