From Shams Momand, Reuters:  NATO helicopters and fighter jets attacked two military outposts in northwest Pakistan on Saturday, killing as many as 28 troops and plunging U.S.-Pakistan relations deeper into crisis.

Pakistan retaliated by shutting down NATO supply routes into Afghanistan, used for sending in nearly half of the alliance’s land shipments. It also said it would ask U.S. forces to quit an air base used for CIA drone strikes on militants.

The attack is the worst incident of its kind since Pakistan uneasily allied itself with Washington following the Sept. 11, 2001 attacks on the United States.

The NATO-led force in Afghanistan confirmed that NATO aircraft had probably killed Pakistani soldiers in an area close to the Afghan-Pakistani border.

"Close air support was called in, in the development of the tactical situation, and it is what highly likely caused the Pakistan casualties," said General Carsten Jacobson, spokesman for the International Security Assistance Force (ISAF).

He added he could not confirm the number of casualties, but ISAF was investigating. "We are aware that Pakistani soldiers perished. We don’t know the size, the magnitude," he said.

Pakistan’s Prime Minister Yusuf Raza Gilani said the killings were "an attack on Pakistan’s sovereignty", adding: "We will not let any harm come to Pakistan’s sovereignty and solidarity. . . ."

A meeting of the cabinet’s defence committee convened by Gilani "decided to close with immediate effect NATO/ISAF logistics supply lines," according to a statement issued by Gilani’s office.

The committee decided to ask the United States to vacate, within 15 days, the Shamsi Air Base, a remote installation in Baluchistan used by U.S. forces for drone strikes which has long been at the centre of a dispute between Islamabad and Washington.

The meeting also decided the government would "revisit and undertake a complete review of all programmes, activities and cooperative arrangements with US/NATO/ISAF, including diplomatic, political, military and intelligence". A similar incident on Sept 30, 2010, which killed two Pakistani service personnel, led to the closure of one of NATO’s supply routes through Pakistan for 10 days. NATO apologised for that incident, which it said happened when NATO gunships mistook warning shots by Pakistani forces for a militant attack.  (photo: Getty)

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