Twenty-three militants and seven Pakistani troops died after the tribesmen ambushed a paramilitary convoy in northwest Pakistan, an army officer said.
Residents in Mohmand, a tribal agency bordering Afghanistan, said the army had opened up with artillery and helicopter gunships after the early morning attack on the convoy.
The convoy was heading to Mohmand's main town of Ghalanai when it came under fire. Militancy has been spreading through northwest Pakistan since mid-2007, after commandos stormed Islamabad's Red Mosque to crush a Taliban-style movement there.
Mohmand adjoins Bajaur, another border tribal region that is a hotbed of support for groups allied to al-Qaeda.