The incident comes as authorities probe reports that Pakistani Taliban chief Hakimullah Mehsud died in a US missile strike elsewhere in the northwest.
Official Abdul Malik says the bodies were displayed Tuesday in the Inayat Kali area in Bajur tribal region.
Bajur was the focus of a previous Pakistani army offensive that seemed largely successful in clearing out the Taliban and Al-Qaeda. But insurgents have recently staged a comeback.
Malik also said security forces had killed eight more militants in overnight raids in the region.
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