Two U.S. service members were killed by enemy forces Sunday while on a mission to take out a mountainous Islamic State stronghold, officials announced Monday morning.
The troops, who were not identified by unit or service, had been accompanying Iraq security forces "during a mission to eliminate an ISIS terrorist stronghold in a mountainous area of north central Iraq," officials with Operation Inherent Resolve said in a news release.
In a later statement, officials said that additional forces were launched the evening of March 8 to recover the two fallen troops in the southern Makhmur Mountains in Iraq, reported by The New York Times to be members of a Marine Special Operations Team.
The location was roughly 60 kilometers, or about 37 miles, south of Erbil, the capital of the Kurdistan region.
"The forces trekked through mountainous terrain and eliminated four hostile ISIS fighters who were barricaded in the caves. The recovery took approximately six hours," Col. Myles B. Caggins III, a spokesman for the OIR coalition, said in a statement.
Officials estimated that between 15 and 19 ISIS fighters were killed in action during the course of the mission.
"The Makhmur Mountains are historically known to be an ISIS safe haven. However, there is no safe place for ISIS to hide," officials said. "The Coalition, alongside our partner forces, will continue to hunt the remnants of the illegitimate caliphate in order to disrupt any effort to resurge."
Related: Investigation to Look Into Possibility That Marine in Iraq Was Killed by Friendly Fire
The death of the two service members is the first deadly hostile incident for U.S. troops this year in the fight against ISIS in Iraq and Syria. The last hostile U.S. military death while supporting Operation Inherent Resolve was on Aug. 10, 2019, when a Marine Raider, Gunnery Sgt. Scott Koppenhafer, was killed alongside an American contractor during a mission to track an ISIS suspect in Iraq's Nineveh province.
Koppenhafer's death was later investigated as a possible friendly fire incident; ultimately, Defense Department officials said no evidence was found to support that possibility.
There are roughly 5,200 U.S. troops deployed to Iraq in support of continued efforts to flush out remaining ISIS fighters in the country.
-- Hope Hodge Seck can be reached at hope.seck@military.com. Follow her on Twitter at @HopeSeck.
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