Eight American soldiers and as many as seven Afghan troops have been killed in a Taliban attack on two outposts in northeastern Afghanistan near the Pakistani border, the U.S. military says.

The Americans and Afghans repelled the attack and "inflicted heavy enemy casualties," the U.S. military said in a statement released Sunday.

About 300 militia fighters from a mosque and a nearby village in the mountainous province of Nuristan attacked the outposts before dawn Saturday, sparking the day-long battle. They first stormed one police post, then another run by NATO forces.

"This was a complex attack in a difficult area," said Col. Randy George, commander of U.S. forces in the region. "Both the U.S. and Afghan soldiers fought bravely together. I am extremely proud of their professionalism and bravery."

The Taliban claimed responsibility for the attack, the deadliest for NATO and aligned forces since a similar raid in July 2008 killed nine U.S. soldiers in the same mountainous region.

In a separate incident, an Afghan police officer opened fire on U.S. soldiers in the central province of Wardak on Saturday, killing two and injuring three.

Afghan officials said the Afghan officer had been conducting a joint operation with U.S. troops.

Last week, Gen. Stanley McChrystal, the commander of U.S. and NATO forces in Afghanistan, said the military situation in the country is in "some ways deteriorating," and that foreign forces must "redefine" their strategy.

McChrystal said he believes that plan should not only focus on the threat of al-Qaeda and the Taliban, but also greater protection and stability for the Afghan population.

With files from The Associated Press