U.S.-led coalition warplanes attacked militants withdrawing from a clash with police in the mountains of eastern Afghanistan on Tuesday, killing 15 of them, officials said.

Ismatullah Alizai, police chief of Paktia province, said no one was hurt in the initial battle at the government headquarters in the town of Sayid Karam.

1st Lt. Nathan Perry, a spokesman for the U.S.-led coalition, said an unmanned drone identified the retreating militants and that "close air support was used to engage and kill" them early Tuesday.

Alizai said 15 militants were killed. He said all the bodies as well as four wounded fighters were at a local hospital.

Fighting between Taliban-led insurgents and foreign and government forces is surging across the south and east of Afghanistan. Nearly 2,000 people have died in insurgency-related violence so far this year.

The coalition said Monday that it had killed about 55 insurgents in a two-day battle in neighboring Paktika province. Paktika borders Pakistan, where some Taliban and al-Qaida militants are based.

Officials also reported an ambush Tuesday about 40 miles (70 kilometers) south of Kabul of a convoy of trucks carrying supplies to foreign forces.

Mohabullah, a senior police official in Wardak province who uses one name, said government and foreign forces, including aircraft, rushed to the convoy's aid.

A NATO spokesman confirmed the attack and said there were reports of casualties, but had no details. He asked not to be named, citing internal rules.

In the remote northeastern province of Nuristan, police said foreign and Afghan troops had been battling rebels in the mountains north of the main town of Kamdesh for three days.

Ghulam Farooq, the deputy provincial police chief, said four militants were killed on Monday.

Perry reported four separate clashes in the area early Sunday. NATO troops exchanged fire with insurgents and called in air support, he said. Reports indicate "several" militants died, he said.

Meanwhile, a female police officer was fatally shot by two assailants on a motorcycle in western Afghanistan, police said.

The gunmen fired three bullets into the officer's torso as she walked home from work Monday in Guzara district of Herat province, police spokesman Raouf Ahmadi said.

Two suspects have been arrested, Ahmadi said. The motive was unclear.