Capt. Justin Brockhoff, a spokesman for the coalition, said the fighting started during an overnight operation targeting a Taliban leader in the Kuz Kunar district of Nangarhar province. The joint force made up of Afghan and coalition troops came under fire and insurgents refused requests to come out of the building, he said.

The fighting ended Sunday with a NATO airstrike, he said, adding that there were no casualties among civilians or security forces. The insurgents were armed with machine guns, assault rifles and rocket-propelled grenades.

"As Afghan members of the security force attempted to clear the building, they were met with continuing insurgent fire," Brockhoff said. The coalition and Afghan forces eventually called in an airstrike, which "killed several more insurgents and destroyed the building," he said.

Ahmad Zia Abdulzai, a spokesman for the Nangarhar provincial governor, said the bodies of 13 insurgents have been found so far. He said the building occupied by the Taliban was school which was empty because the students are on summer break.

The fighting came as NATO handed over control for security in central Bamiyan province to Afghan security forces — the first of seven areas to be transferred to Afghan control. The province, along with Panjshir in the east, has seen little to no fighting since the overthrow of the Taliban nearly 10 years ago. Bamiyan and Panjshir are the only two provinces that will transition in their entirety and barely had any coalition troops present there.