A citizens' militia trying to drive out the Taliban killed seven militants in a two-hour firefight in Pakistan's troubled northwest, police said Sunday.

Ejaz Ahmed, police chief in the Upper Dir region, said another militant was injured in the fighting late Saturday night near the village of Patrak, about four miles east of Dir Khas, the region's main town and district headquarters.

Several civilian militias, known as lashkars, have emerged in Upper Dir since a suicide bombing on a mosque two weeks ago that was blamed on the Taliban killed at least 33 people. The militias carry out patrols and have been pursuing remnants of Taliban who had tried to expand their influence into the area.

Ahmed said scores of militants have been trapped and killed by the militias in several villages, with police cutting off escape routes. The Taliban who were killed Saturday had been trying to flee when they came across the militiamen and opened fire, he said.

"Due to heavy losses, militants have been attempting to escape the area under cover of dark, and last night's incident was one such attempt," Ahmed said. He said no civilians were killed in the fighting.

The report could not immediately be confirmed due to military restrictions on media access to the area.

In the most striking example of growing anti-Taliban sentiment, up to 1,600 tribesmen in Upper Dir cleared three villages of Taliban fighters two weeks ago, killing at least six militants.

There were no immediate reports on fresh fighting in the nearby South Waziristan tribal area, where shelling and bombing of suspected militant targets has been increased and ground troops have been moving into position in the past week since the government announced the military would go after Pakistan's Taliban commander, Baitullah Mehsud.

A military statement Saturday said 37 extremists died when troops retaliated after the militants tried to block the main South Waziristan road near the town of Sarwaki. They were the first militant casualties of the offensive in South Waziristan to be confirmed by the army.

South Waziristan is Mehsud's tribal stronghold, a chunk of the remote and rugged mountainous region along Pakistan's northwestern border with Afghanistan where heavily armed tribesmen hold sway and Al Qaeda and Taliban leaders are believed to be hiding.

Pakistan is shifting the focus in its fight against militancy from the northwestern Swat Valley, where troops have been pushing Taliban fighters back for almost two months, to a new and much tougher battleground in the Afghan border region.

Washington supports both operations, and sees them as a measure of nuclear-armed Pakistan's resolve to take on a growing insurgency after years of failed military campaigns and faltering peace deals. The battle in the tribal region could also help the war in Afghanistan because the area has been used by militants to launch cross-border attacks on U.S. and other troops.