The NATO-led mission in Afghanistan says a U.S. soldier was killed during an anti-Taliban operation near Lashkar Gah, the capital of the southern province of Helmand.
A coalition statement said another U.S. soldier and six Afghan soldiers were wounded in the August 23 incident.
General John W. Nicolson, the commander of U.S. forces in Afghanistan and the NATO-led Resolute Support mission, confirmed the casualties.
In a statement, the U.S. general's press office said the U.S. troops were conducting "train, advise, and assist" activities with Afghan soldiers when their patrol triggered an improvised explosive device.
About 100 U.S. troops were deployed to Lashkar Gah this week as reinforcement in what the U.S. military described as a "temporary effort," though authorities declined to say how long the deployment was expected to last.
Since late July, the Taliban has seized swathes of territory across Helmand Province and encroached on the provincial capital, raising concern about a possible Taliban attack on Lashkar Gah.