Two Afghan officials working in the border area where the attack took place said Sunday that the joint force was targeting Taliban forces in the area when it received fire from a Pakistan military outpost. That prompted the coalition force to call for an air attack on the Pakistani posts, said an Afghan Border Police official in the area. Pakistani officials were informed of the operation before it took place, he said.

“There was firing coming from the position against Afghan army soldiers who requested support and this is what happened,” said a third Afghan official in Kabul, where Gen. Allen met with top government leaders for a special security meeting to discuss the incident. The Afghan official in Kabul said the government believes that the fire came from the Pakistan base—and not from insurgents operating nearby.

That view was bolstered by one Western official who discussed the attack with military officials in Kabul on Sunday.

“They were fired on from a Pakistani army base,” the Western official in Kabul said. “It was a defensive action.”…

“It was a situation where insurgent forces butted right up against a Pakistani border post and used that as a firing position. When we fired back, we hit Pakistani security forces. This is a possibility we’re circulating here for Saturday’s incident,” the official said.