Pentagon officials say that a roadside bomb killed five U.S. troops in southern Afghanistan today.
The NATO-led International Security Assistance Force (ISAF) had previously said that five foreign troops had been killed, but declined to give their nationalities.
A Pentagon spokesman said they were American troops.
Meanwhile, the Taliban have insisted that the fighters who shot down a U.S. helicopter last weekend are still alive.
The U.S. military said that those responsible for the downing of the helicopter, which killed 30 U.S. troops along with seven Afghan soldiers and an Afghan interpreter, were killed in an air strike on August 8.
The incident was the single biggest loss of American life in the 10-year-old conflict in Afghanistan.
But a Taliban spokesman, Zabiullah Mujahid, said the fighters who carried out the attack in Wardak Province were still alive.
He said the U.S. air strike had killed four fighters, but that they had not been the ones who downed the helicopter.
compiled from agency reports