Several hundred militants from Afghanistan launched a pre-dawn cross-border raid on Pakistani paramilitary posts and civilian settlements, killing at least 36 people, government and security officials said.
Soldiers of the Chitral Scouts and police were among the dead in the string of attacks that began with an assault on paramilitary check posts in the border village of Arandu in the northwest just across from Afghanistan's Nuristan province.
"Reportedly, terrorists from Swat, Dir and Bajur organised by Fazullah and Maulvi Faqir Mohammad with local Afghans have attacked the security forces posts," a military statement said, referring to northwestern Pakistani regions and senior Pakistani Taliban commanders.
Many Pakistani Taliban fighters fled to Afghanistan in the face of army offensives and have joined allies there to regroup and threaten Pakistani border regions, analysts say.
The military operations in the country's northwest have inflicted heavy losses on them, but insurgents have proved resilience with intermittent attacks and suicide bombings.
A senior Chitral Scouts official said 26 soldiers and 10 border police were killed.
Twenty militants were also reportedly killed when insurgents attacked seven military check posts, the military statement said. There was no independent verification of the militant death toll.
The military statement put the security forces death toll to at least 25.
Troops blew up two bridges in the border region to stem the militants' incursion.
Cross-border raids have raised tension between Pakistan and Afghanistan in recent months as they battle protracted insurgencies by Taliban and al-Qaeda-linked militants.
Some 27 Pakistani servicemen were killed and 45 militants died in clashes in July when some 600 militants from Afghanistan attacked two Pakistani villages in the Dir region, also in the country's northwest. Pakistani Taliban later claimed responsibility for the Dir attack, part of seemingly new militant strategy of carrying out large-scale attacks on government and army targets.
Militants have largely relied on a campaign of suicide and bomb attacks that have killed thousands of people across the country.
Pakistan blames Afghanistan for giving refuge to militants on its side of the border, leaving its troops to counter-attack when it chases them out of the tribal areas and into Afghanistan.
Kabul in turn has blamed Pakistan in recent months for killing dozens of civilians in cross-border shelling.
Reuters