Two soldiers were wounded in the attack. Pentagon officials did not say which militant group in Afghanistan was responsible. He was assigned to the 1st Brigade Combat Team of the 1st Armored Division at Fort Bliss, Texas.
Kirkpatrick's death brings the total number of USA casualties in Afghanistan for this year to seven.
There has been fierce fighting in Helmand where Afghan security forces have been locked in constant clashes with Taliban insurgents, who have managed to reestablish a significant presence in the area.
Few details surrounding Kirkpatrick's death have been provided at this point.
"We will keep [Kirkpatrick's] family in our thoughts and prayers as we reflect on the sacrifice he and others have made to secure our freedoms and help make Afghanistan a better place", Army Gen. John Nicholson, the top USA commander in Afghanistan, said in a prepared statement.
The battalion deployed to Helmand Province, Afghanistan earlier this year for a "train, advise, and assist mission", an effort to continue training and supporting Afghan security forces in a war that is about to complete its 16th year, according to the Department of Defense. Hansen B. Kirkpatrick, 19. The senators held a press conference in Afghanistan, where they called on the Donald Trump administration to fill vacant embassy and State Department positions to better address the country's military and political crises.
The United States has about 8,400 troops deployed to Afghanistan.
The U.S.is now weighing whether to send thousands of additional troops to Afghanistan to change the tides of conflict, which Defense Secretary Jim Mattis has said the U.S.is "not winning". He's said this strategy will take a regional approach to the conflict, and address shortfalls in the Afghan military's institutions.
Last month, President Trump gave Defense Secretary Jim Mattis the authority to set USA troop levels in Afghanistan.
USA soldiers returned fire killing two militants.
Safi further added that the operations are being conducted with the support of the foreign forces based in the country, who are mainly providing air support to the Afghan troops and Special Forces on the ground.