Pakistan, U.S. Trade Fire at Afghan Border

— -- Pakistani soldiers fired at American reconnaissance helicopters that were escorting Afghan and U.S. ground troops along the volatile border Thursday, sparking a ground battle between the American and Pakistani soldiers, officials said.

Attempting to downplay the incident, Pakistan's president said only "flares" were fired.

But the five-minute exchange could heighten tensions at a time when the U.S. is stepping up cross-border operations in a region known as a haven for Taliban and al-Qaida militants.

Two American OH-58 reconnaissance helicopters, known as Kiowas, were on a routine afternoon patrol in the eastern province of Khost when they received small arms fire from the Pakistani border post, said Tech Sgt. Kevin Wallace, a U.S. military spokesman in Bagram. There was no damage to aircraft or crew, officials said.

U.S. Central Command spokesman Rear Adm. Greg Smith said the helicopters had been escorting U.S. troops and Afghan border police. When the helicopters were fired on, the U.S. ground forces fired rounds meant not to hit the Pakistani troops, but "to make certain that they realized they should stop shooting," Smith said from Centcom headquarters in Florida.

Smith said the joint patrol was about one mile (1.5 kilometers) inside Afghanistan.

The Pakistani military disputed the U.S. version, saying its troops fired warning shots when the two helicopters crossed over the border -- and that the U.S. helicopters fired back.

"When the helicopters passed over our border post and were well within Paskitani territory, own security forces fires anticipatory warning shots. On this, the helicopters returned fire and flew back," a Pakistani military statement said.