Marine Coprs
Lance Cpl. Sean Neal (not pictured) is the first U.S. serviceman to die in an ISIS mission. He was 19. Reuters

Marine Lance Cpl. Sean Neal was the first service member to die in Iraq on a mission against Islamic State militants, the Washington Post reported. He was 19. ‘

The California native died in Baghdad Thursday during a “noncombat incident,” the Pentagon said. Further details were not released. The military is investigating the incident, the Marine Corps Times said.

Neal’s death was the first U.S. casualty in Iraq since the Obama administration began its “Inherent Resolve” mission, the Post said. There is a growing number of military personnel on the ground in Iraq, and the U.S. has launched airstrikes against the extremist group in Iraq and Syria as part of the mission.

Neal joined the Marine Corps in July 2013, the Marine Corps Times reported. He was serving on his first mission as a mortarman with 2nd Battalion, 7th Marines, an infantry unit based in Twentynine Palms, California.

Though Neal’s death is officially the first among servicemen fighting ISIS, although another Marine -- Cpl. Jordan Spears -- was lost at sea in the Persian Gulf Oct. 2.

“U.S. Navy, Marine Corps and Coast Guard personnel conducted an extensive search of the area using all available assets, which continued throughout the night and the next day,” U.S. Naval Forces Central Command said in a statement at the time.

More than 4,000 U.S. military service members have been killed in Iraq after the U.S.-led invasion in 2003.

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