Pakistan - Pakistani security forces backed by tanks and artillery attacked Taliban positions in the northwest of the country, killing 22 militants, a senior police official on Monday.

The attack was part of a broader campaign against militants in Pakistan, a regional ally which Washington sees as key to defeating the Taliban in Afghanistan.

Fighting erupted on Sunday night after an assault on militants in the village of Shahukhel, which borders the Taliban stronghold of Orakzai tribal region.

There has been fierce fighting throughout the night. Militants fired rocket propelled grenades while troops responded with artillery and tank fire, local police official Fareed Khattak told Reuters.

We have a figure of 22 militants dead and 14 arrested.

Pakistan's army went on the offensive in the ethnic Pashtun tribal region of South Waziristan on the Afghan border on October 17, aiming to root out militants who stepped up their war against the security forces in 2007.

The campaign could backfire if Taliban fighters gain an edge by sucking Pakistani troops deep into rugged mountains in the area.

The United States, weighing options for how to stem an intensifying insurgency in Afghanistan, has welcomed the Waziristan offensive, hoping it will help root out fighters from the region described as a global hub for militants.

But Washington is keen to see Pakistan also tackle Afghan Taliban factions based in lawless enclaves along the border.

Khattak said forces had entered the lawless Orakzai region where many Taliban insurgents had fled. Now helicopter gunships are striking Taliban hideouts in the agency, he said.

A Taliban spokesman in Orakzai, Zia-ur-Rehman, said both sides suffered heavy casualties in the clashes.

According to the military, more than 500 Taliban have been killed in the South Waziristan assault while 70 soldiers have been killed.

There has been no independent verification of casualties as reporters and other independent observers are not allowed into the conflict zone except on an occasional trip with the military.

(Additional reporting by Javed Hussain; Writing by Kamran Haider; Editing by Michael Georgy and Jeremy Laurence)

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