At least 27 Pakistanis, including four civilians, were killed in the fighting, as were 45 insurgents, local police officials said. The dead included two women, a child and a prayer leader in the town of Shaltalo.
The insurgent fighters blew up at least two schools and stole weapons from the Pakistani checkpoint, according to local officials in the area, who said the militants were thought to be Afghans and Pakistanis.
Pakistan’s foreign office said late Thursday that it had complained about the attack to Afghanistan and urged “stern action” by the Afghan army and NATO forces against militants and their hideouts in Afghanistan.
Omar Hassan Ahravi, who identified himself as a spokesman for the Pakistani Taliban in the nearby Malakand region, told some local reporters that his organization had carried out the attack “with Afghan friends.”
Ahravi said the militants managed to seize Pakistani antiaircraft weapons.
The mountainous border between Pakistan and Afghanistan is famously porous, making it easy for Afghan fighters based in Pakistan to cross over for attacks on coalition forces. But fighters based in Afghanistan rarely stage missions on the Pakistan side of the border. Pakistani security officials said Thursday that they thought the Upper Dir attack might have been carried out by Pakistani militants who previously fled across the frontier during military offensives.
Police in Upper Dir, which lies outside Pakistan’s tribal areas in Khyber Pakhtunkhwa province, said the majority of about 300 fighters had retreated back into Afghanistan by Wednesday afternoon.
The confrontation demonstrated the continued strength of Islamist militants along the Afghanistan-Pakistan frontier, in spite of several recent Pakistani military offensives on Pakistani soil and the presence of NATO troops across the border.
On Wednesday, the Pakistani general who commands troops in the restive northwest announced plans for a new offensive in Kurram, a tribal area farther south along the border. Kurram borders North Waziristan, a militant hub that the United States wants Pakistan to attack. But the general and other Pakistani officials said Wednesday that they have no imminent plans to do so.
“There is no change in North Waziristan in past months and weeks,” Lt. Gen. Asif Yasin Malik said. “We will undertake an operation when we want to, when it’s in the national interest.”
Witnesses said the fighters involved in the clashes were wearing fatigues. Some said the uniforms resembled those worn by Pakistani soldiers, and others said they looked like the uniforms of NATO troops.
Khan is a special correspondent. Correspondent Karin Brulliard in Islamabad, Pakistan, contributed to this report.