A U.S. military HH-60 Black Hawk chopper participating in the anti-Islamic State (ISIS/ISIL) war in the Middle East crashed in western Iraq near the country’s border with Syria this week, killing all seven American service members on board, according to the Pentagon.

Citing anonymous U.S. Department of Defense (DOD) officials, the Associated Press (AP) notes that while the incident is under investigation, it did not appear to be the result of jihadi activity in the region.

U.S. Central Command (CENTCOM)—charged with overseeing American military activity in the Middle East—also stated the crash “does not appear to be a result of enemy activity.”

Nevertheless, AP learned:

The helicopter was used by the Air Force for combat search and rescue, and was in transit from one location to another when it went down Thursday afternoon near the town of Qaim in Anbar Province.

The Pentagon said an accompanying U.S. helicopter immediately reported the crash and a quick-reaction force comprised of Iraqi security forces and Coalition members secured the scene.

Fox News describes the crash as “the first deadly aviation crash for the U.S. military in the war against ISIS in Iraq and Syria since American involvement began in 2014.”

U.S. Army Brig. Gen. Jonathan P. Braga, the director of operations in the war against ISIS in Iraq and Syria, commented on the incident on the record via the statement issued by CENTCOM, praising the deceased troops for their sacrifice.

The top U.S. general declared:

This tragedy reminds us of the risks our men and women face every day in service of our nations. We are thinking of the loved ones of these service members today.

We are grateful to the Iraqi Security Forces for their immediate assistance in response to this tragic incident. Iraqi Security Forces continue to demonstrate their professionalism, capabilities, and flexibility as we continue the fight towards a lasting defeat of [ISIS].

DOD is expected to release the name of the fallen soldiers after it notifies the next of kin.

President Trump also expressed his condolences via Twitter on Friday.

“Our thoughts and prayers go out to the families, and loved ones of the brave troops lost in the helicopter crash on the Iraq-Syria border yesterday. Their sacrifice in service to our country will never be forgotten,” wrote the commander-in-chief, referring to the seven U.S. airmen killed.

“The incident marked the second aircraft crash for the military in two days,” reports Fox News, it adds, “A U.S. Navy F/A-18F Super Hornet jet crashed off the coast of Key West, Florida, on Wednesday, killing both a pilot and a weapons systems officer.”

Although Iraqi leaders have declared a victory of ISIS, the jihadist organization remains a threat, according to the U.S. military.