KABUL - NATO forces said Tuesday they had killed more that 100 fighters in a huge weekend battle in eastern Afghanistan in which eight Americans died, the deadliest firefight for U.S. troops in more than a year.

The revised enemy death toll gives an idea of the scale of the battle, one of the biggest of the eight-year-old war, in which hundreds of fighters armed with machine guns, rifles and rocket-propelled grenades attempted to storm remote outposts.

A more detailed battlefield assessment following the October 3 attack in Nuristan has determined that enemy forces suffered more than 100 dead during the well-coordinated defense, significantly higher losses than originally thought, NATO said in a statement.

The fighters launched their assault on two remote outposts in Nuristan province Saturday, triggering the 13-hour battle in a part of the country U.S. forces had already planned to abandon under a new strategy calling for a focus on population centres.

At least two Afghan soldiers died in the battle and authorities said they had lost contact with police in the area and did not know if they were captured or deserted.

The NATO statement said Western forces had concluded the attackers were local militants operating with the help of the Taliban and the Hezb-i-Islami group led by former anti-Soviet Mujahideen commander Gulbuddin Hekmatyar.

Since the weekend assault, Afghan authorities say U.S. and Afghan forces have mounted a number of operations to retake areas held by the Taliban. U.S. officials say operations have taken place in the area but have not give further details.

(Reporting by Peter Graff; Editing by Nick Macfie)