Security forces backed by helicopter gunships on Sunday killed 10 militant followers of a pro-Taliban cleric in the Swat valley in northwestern Pakistan, sparking tensions that prompted hundreds of people to flee from the region.

Police and paramilitary troops moved into areas dominated by militants near Maulana Fazlullah's stronghold at Imamdheri in the North West Frontier Province after the rebels carried out pre-dawn attacks on police and paramilitary personnel.

Military spokesman Maj Gen Waheed Arshad said 10 militants were killed in operations by the police and paramilitary forces. There was no information of casualties among the security forces.

Helicopter gunships provided security to paramilitary Frontier Corps troops, who also used mortars to target militant positions. Army troops deployed in the area are on standby and would be used only if they were called in by the local administration, he said.

The operation, he said, would continue till the militants were evicted from the area and peace is restored.

Asked if the troops are targeting Fazlullah, who has gone into hiding, Arshad said: "All militants and extremists are going to be targeted. And he is one of them."

"These are the same militants who were terrorizing innocent civilians and beheaded civilians and dragged their bodies. I think they have got what they deserved," Arshad said.

The militants had beheaded six security personnel and executed nine civilians on Friday in retaliation for an attack by troops on Fazlullah's madrassa at Imamdheri. The militants are demanding imposition of Islamic law in the region.