A U.S. soldier stands guard in the Achin district of Nangarhar province in eastern Afghanistan on April 15, 2017. Parwiz Parwiz / Reuters

The Pentagon said Friday it’s investigating the deaths of two American service members who may have been the target of “friendly fire” during an operation targeting Islamic State militants in eastern Afghanistan.

The Department of Defense identified the Army Rangers, both members of the Army’s 3rd Battalion, 75th Ranger Regiment, as Sgt. Joshua P. Rodgers, 22, and Sgt. Cameron H. Thomas, 23. Both were killed Wednesday night during a mission targeting ISIS militants in Afghanistan’s eastern Nangarhar province, where much of the U.S.’s fight against ISIS militants has taken place.

Pentagon spokesman Captain Jeff Davis told reporters Friday that while initial indications pointed to friendly fire, there was “no indications it was intentional,” adding:  “War is a very difficult thing, in the heat of battle, in the fog of war the possibility always exists for friendly fire, and that may have been what happened here and that is what we are looking into with this investigation.”

Defense Secretary Jim Mattis said in a statement Friday that Rodgers and Thomas “proved themselves willing to go into danger and impose a brutal cost on enemies in their path,” adding: “They carried out their operation against ISIS-K in Afghanistan before making the ultimate sacrifice to defend our nation and our freedoms. Our nation owes them an irredeemable debt, and we give our deepest condolences to their families.”

ISIS-K refers to the ISIS-Khorasan group, the Islamic State’s branch in Afghanistan.

The deaths of Rodgers and Thomas mark the second and third fatalities in Afghanistan this year. The investigation into their deaths is the second such inquiry into a military fatality under the Trump administration: The death of Navy SEAL Ryan Owens in January during a “boots-on-the-ground” raid in Yemen also prompted an investigation.

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