The clashes in the town of Miran Shah caused hundreds of people to flee the area.
There were no immediate reports of casualties.
The clash follows a raid by Pakistani security forces on a militant hideout on March 1 in the village of Saidgai in the same area. The raid killed dozens of suspected insurgents.
Pakistani forces are battling Al-Qaeda and Taliban militants who move back and forth from Afghanistan into Pakistan's tribal border areas as well as their local supporters.
RFE/RL Afghanistan Report
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