The alliance force did not provide further details regarding the nationality of the Thursday casualties.
Bomb and shooting attacks on foreign troops hit their peak at this time of the year in the war-torn country by Taliban militants.
According to the website icasualties.org, a total of 246 foreign troops, mostly US personnel, have lost their lives in Afghanistan so far this year.
The rising death toll for the US-led forces has increased anger in the US and other countries contributing to the prolonged war in Afghanistan.
The 2001-present US-led war in Afghanistan, which has caused record-high civilian and military casualties, has become the longest military conflict in the American history.
Washington invaded Afghanistan under the pretext of combating terrorism.
Insecurity continues to rise across Afghanistan, despite the presence of thousands of US-led forces in the country.
PG/SS