Another US-led occupying troops was killed in a similar incident in southern Afghanistan earlier in the day.
The western occupying force, however, did not provide details of the incidents, and did not announce the name or nationality of the victims.
According to official figures released by the website icasualties.org, a total of 525 foreign troops have lost their lives in war-battered Afghanistan so far this year.
Last year, nonetheless, remains the deadliest year for foreign military casualties with a death toll of 711. The number eclipsed the previous record of 521 set in 2009.
The increasing number of military casualties in Afghanistan has caused widespread anger in the US and other NATO member states, undermining public support for the Afghan war.
Insecurity continues to rise across Afghanistan due to the presence of nearly 150,000 US-led occupying forces in the Asian country.