Two Pakistani soldiers were mistakenly killed Monday by U.S. forces who were attacked near the border in Afghanistan, American and Pakistani officials said.

U.S. troops were on a morning patrol near Orgun (search), in eastern Afghanistan's Paktika province, when they were shot at by enemy forces who then fled toward Pakistan, said a statement by the U.S. Central Command, based in Tampa, Fla.

American forces on the ground and in the air returned fire, mistakenly killing two Pakistani soldiers and wounding another, the statement said, adding that the incident is under investigation.

In Pakistan, the military said U.S. forces fired on the Imal Khel post in Pakistan's North Waziristan tribal region, about 165 miles southwest of Peshawar, but provided no further details.

"A strong protest has been lodged with U.S. authorities about the incident," the military said.

Taliban and Al Qaeda fugitives are believed to have sought refuge in the tribal region near the Afghanistan border.

A U.S.-led coalition ousted the Taliban (search) from Afghanistan in late 2001, but American forces remain in the country searching for remnants of the regime and their allies in Usama bin Laden's Al Qaeda terror network.