There are conflicting reports on how Malik Agha was abducted Friday in the Ataghar district of Zabul, reported the BBC Saturday.
Taliban spokesman Abdul Latif Hakimi was quoted as saying the Taliban had hanged Agha because he said he was a spy for America, the BBC said.
The body of Agha was found later in the day Friday.
The Taliban have allegedly killed a number of Karzai's supporters as Afghanistan prepares for September's parliamentary elections.
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