Amir Mohammad Akhund, the deputy governor of Helmand Province, said the attack occurred on a road often patrolled by government militia and police, who were likely the intended target.
Violence has increased across southern Afghanistan during the past year, much of it blamed on feuding drug gangs and Taliban rebels.
The bloodshed has left large areas off-limits to aid workers and raised concerns for the country four years after the ouster of the Taliban in a U.S.-led invasion.
RFE/RL Afghanistan Report
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