Six US soldiers were killed in action after a US KC-135 refueling aircraft went down in western Iraq during a collision between it and a second aircraft during Operation Epic Fury, US Central Command (CENTCOM) confirmed on Friday night.
The circumstances of the incident are under investigation, and the identities of the soldiers have not been released yet.
CENTCOM assured that the incident occured in friendly airspace, and was not due to hostile or friendly fire.
The refueler went down near Turaibil, along the Iraqi-Jordanian border, CBS News reported, citing an Iraqi intelligence source.
A US official, speaking to Reuters on the condition of anonymity, said that the other aircraft involved in the crash was also a KC-135.
Flight tracking service FlightRadar24 showed that the second KC-135 had declared an emergency before landing safely in Israel earlier in the day.
The Islamic Resistance in Iraq, an umbrella group of Iran-backed armed factions, claimed responsibility for downing the US military aircraft, Reuters reported.
The group said in a statement it had shot down the KC-135 aircraft "in defense of our country's sovereignty and airspace."
Kuwait accidentally downs three US fighter jets
This marks the fourth US aircraft to be lost as part of Operation Epic Fury.
Last week, Kuwait's air defenses mistakenly shot down three US F-15 fighter jets during active combat, which CENTCOM at the time described as an apparent friendly‐fire incident.
All six crew members ejected from the aircraft safely and were recovered in stable condition.
Reuters and Jerusalem Post Staff contributed to this story.