Pakistani troops have fired mortar shells at a radio transmitter operated by a Muslim cleric in the town of Bara in north-west Pakistan.
At least five people were injured by the shelling which put the transmitter out of action, reports say.
Earlier this week, 25 people were killed in clashes between supporters of two clerics.
Pakistani security forces intervened and ordered both clerics to shut down their radio transmitters.
Mufti Munir Shakir's radio station -which was hit by Pakistani forces - had criticised his rival cleric Pir Saifur Rehman, who had also set up a small FM radio station.
Correspondents say the rivalry between the two clerics had nothing to do with a security operation against pro-Taleban militants in nearby Waziristan and is more about territorial control and enforcing the conflicting Muslim beliefs of the two rival clerics.
Bara is the main trade route between Pakistan and Afghanistan and is an important town in Khyber agency which borders Afghanistan. The town is also said to be a hub for smuggled goods.
Both clerics had been operating illegal FM stations to broadcast their religious beliefs and denounce the rival group as heretics.