NATO says a man in Afghan army uniform has opened fire on US forces in the troubled southern Afghanistan, killing at least one soldier.
NATO said in a statement that the attacker was then shot dead by coalition forces on the spot.
The western military alliance says an investigation has been launched into the incident to determine the reason and motive behind the killing.
Anti-American sentiment has hit unprecedented levels since the burning of the Holy Quran and the massacre of Afghan civilians by US soldiers over the past months.
The incident also comes as the fighting between foreign forces and Taliban militants has escalated in various parts of the country.
Earlier in the day, three US soldiers were killed after a bomb struck a US patrol in the Panjawi district of the Afghanistan’s southern province of Kandahar.
The southern regions of Afghanistan, including Kandahar, are among the most dangerous parts of the war-ravaged country for the US-led foreign troops.
According to the icasualties.org
website, nearly 130 US-led troops have been killed in Afghanistan so far this year.
Insecurity continues to climb across Afghanistan despite the continued presence of nearly 130,000 US-led forces in the Asian country.
The rising number of military casualties in Afghanistan has caused widespread anger in the US and other members of the Western military alliance of NATO, undermining public support for the US-led war.