Ghulam Dusthaqir Azad, governor of the southwestern province of Nimroz, said the four were arrested on 30 January. He said the four are suspected of plotting attacks in Afghan territory.
The provincial police chief, Khalili Bakhtiar, says they may have links to Taliban militants in the southern Afghan city of Kandahar.
Afghan and U.S. military officials have long said that foreign militants are helping the Taliban wage their insurgency in Afghanistan.
RFE/RL Afghanistan Report
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