Sgt. Leandro Jasso was killed Nov. 24 in Nimroz Province in western Afghanistan during a joint U.S-Afghan assault on al Qaeda positions, officials said.
"An initial review indicates Sgt. Jasso was likely accidentally shot by our Afghan partner force, said a statement from Resolute Support, the name for the NATO mission in Afghanistan. "There are no indications he was shot intentionally."
"The loss of Sgt. Jasso is felt by his family and loved ones, by all who served with him and by all on this mission to protect our country and our allies," said Gen. Scott Miller, the commander of Resolute Support and United States Forces - Afghanistan.
"Early interviews indicate the tragic accident occurred when the partnered force became engaged in a close-quarter battle during an assault on one of multiple barricaded al Qaeda shooters," the statement added.
"Sgt. Jasso was killed defending our nation, fighting al Qaeda alongside our Afghan partners," Gen. Miller added. "All of us, and throughout our coalition of 41 nations, recognize the threats posed by groups such as al Qaeda and ISIS and are determined to fight them here."
Jasso, 25, was a member of the Army's elite 75th Ranger Regiment and was on his third deployment to Afghanistan. Resolute Support had initially said that he had been killed in close combat and had later died from his wounds after being medically evacuated.
His remains returned to the United States late Monday night at Dover Air Force Base in Delaware.
Friendly fire deaths are rare and can result from close combat situations on the ground or from airstrikes involving close air support.
Jasso joined the Army in August 2012. At the time of his death, he was serving as the team leader for Alpha Company in his Ranger Regiment's 2nd Battalion based out of Joint Base Lewis-McChord in Washington state.
He is the 10th U.S. service member to be killed in Afghanistan this year and the second in November.
The U.S. currently has approximately 14,000 service members training and assisting the Afghan government in their fight against extremist groups.
ABC News' Elizabeth McLaughlin contributed to this report.