A policeman in Kandahar Province's Spin Boldak district, Mohammad Asif Khan, said the attack occurred on a main highway in the district, where the company was providing security for road construction projects.
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Three security guards were killed, along with their driver.
Meanwhile, reports say a explosion rocked the center of the capital Kabul today.
It is not immediately clear what caused the blast, or whether there were casualties.
(AP, AFP)
RFE/RL Afghanistan Report
RFE/RL Afghanistan Report

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