Iqbal Khan says another 17 people were wounded in the Tuesday morning blast, which took place on the outskirts of Peshawar on a road leading to neighboring Afghanistan. He says the dead include police, civilians and at least one child.
He says the attack appears to have been carried out by a suicide bomber, who struck as a local police chief arrived at the checkpoint.
No one has claimed the attack.
Peshawar is on the edge of Pakistan's volatile tribal regions, which have long been home to local and foreign Islamic militants.
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