At least three US troops and a military contractor have been killed in a Taliban attack near Bagram Air Base in northern Afghanistan.
The NATO-led Resolute Support mission has said that three other US troops were also wounded in the attack.
Spokesman for US Forces in Afghanistan, Colonel David Butler, said that a car bomb had detonated near the security convoy.
The Taliban claimed to have conducted the attack when a suicide bomber detonated his explosive-filled vehicle.
It said that at least 10 American troops were killed and injured and one armoured personnel carrier was destroyed.
Seven US troops have been killed in Afghanistan so far this year, compared to 12 killed in all of 2018.
Attack was carried out at the time when Taliban leaders are set to meet with Afghan officials in Qatar next week.
Meanwhile, US-led air strikes killed 10 Taliban fighters, including three commanders, in northern Kunduz province.