Pashtun Tahafuz Movement (PTM) leader and Member National Assembly Mohsin Dawar has been arrested from North Waziristan.
He was accused of launching an attack on a Pakistan military check post near the border with Afghanistan.
At least three people were killed in the attack.
Mohsin Dawar and eight others have been nominated in the FIR of the attack.
Mohsin Dawar was at large following the attack on the security check-post in the tribal district.