Pfc. Hansen Kirkpatrick, 19, of Wasilla died Monday in Helmand Province, Afghanistan, the Department of Defense said. Hansen B. Kirkpatrick, 19. "The incident is under investigation".
He is the first fatality since an "insider attack" by an Afghan soldier killed three us service members in May.
The Pentagon is planning to deploy up to 5,000 more troops to Afghanistan to help security forces fighting the Taliban.
Kirkpatrick was assigned to the 1st Battalion, 36th Infantry Regiment, 1st Brigade Combat Team, 1st Armored Division, which deployed out of Fort Bliss, Texas earlier this year as part of Operation Freedom's Sentinel, the US -led training and advising mission in Afghanistan.
Two soldiers were wounded in the attack.
Nawa District, just outside Lashkar Gah, fell to the Taliban past year, and the Afghan forces advised by the Marines have been preparing an operation to retake the district.
Kirkpatrick's death brings the total number of USA casualties in Afghanistan for this year to seven. James C. Bithorn, the executive officer for 1st Armored Division's 1st Brigade.
USA and North Atlantic Treaty Organisation coalition troops are deployed in Helmand to train and advise Afghan security forces struggling against Taliban insurgents. In 2014, North Atlantic Treaty Organisation drew down force levels in the country and Afghan security forces took over front line combat.
The previous US military fatalities in Afghanistan this year included three conventional USA soldiers - Sgt. Eric M. Houck, 25; Sgt. William M. Bays, 29; and Cpl.
Kirkpatrick was the seventh US servicemember killed in action in Afghanistan in 2017. In late April, two United States service members were killed and another wounded while conducting a joint raid in the Achin District in Nangarhar. Sheldon Whitehouse (D-R.I.), Lindsey Graham (R-S.C.) and David Perdue (R-Ga.) - warned that patience among the USA public for the 16-year war could run out without a well articulated strategy. In April, Staff Sgt. Mark R. De Alencar was killed during a firefight with enemy forces, and Sgt. Joshua P. Rodgers and Sgt. Cameron H. Thomas were killed in what's suspected to have been a friendly fire incident.