MARDAN, Pakistan — Pakistan's army vowed Friday to eliminate militants from a northwestern valley but warned that its underequipped troops face thousands of Taliban extremists who have seized towns, planted bombs made from pressure cookers and dragooned children to be suicide bombers.
As air force jets roared overhead and gunbattles raged, terrified civilians from the Swat Valley and neighboring districts accelerated their exodus, with U.N. and Pakistani officials predicting that 1 million refugees will soon burden the turbulent Afghan border region.
The army formally announced Friday that an offensive was under way. It has drawn praise from U.S. officials alarmed at the Taliban's recent advance to within 60 miles of the capital, Islamabad.
Washington says the militants are a threat to nuclear-armed Pakistan itself, as well as to U.S. chances of destroying al-Qaida or of winning the war against their insurgent allies in neighboring Afghanistan.
There are doubts about the ability and resolve of the army and the government to sustain the kind of grinding counterinsurgency warfare needed to defeat extremists whose rhetoric resonates widely in a Muslim nation deeply skeptical of U.S. goals in the region.
Maj. Gen. Athar Abbas, chief army spokesman, said the army needs helicopters, surveillance drones and night-vision equipment, which the United States is scrambling to provide.
Pakistan's army is fighting to wrest Swat and two neighboring districts from militants who dominate the adjoining tribal belt along the Afghan frontier, where U.S. officials say al-Qaida chief Osama bin Laden is likely holed up.
Abbas said Friday that more than 140 militants and two soldiers had been killed in Swat in the last 24 hours, roughly doubling the number of casualties reported so far.
The stream of civilians seeking safety appeared to have intensified, leaving Pakistan facing a humanitarian emergency. The U.N. refugee agency said provincial officials had told them 500,000 had fled, were on the move, or were trying to flee. About a half-million have already been made homeless elsewhere in the border region since August 2008, when the army launched its last major anti-Taliban operation in the Bajur border region.
Tens of thousands of people are trapped in Mingora, Swat's main town. Some have accused the Taliban of not allowing them to leave, perhaps because they want to use them as human shields. Others came under attack even as they fled.