One service member supporting Operation Inherent Resolve died Monday in a non-combat incident, the military said in a statement.
Officials with Combined Joint Task Force-Operation Inherent Resolve provided no further details, including whether the service member was American. Officials also did not say where the incident occurred.
The incident is under investigation.
There has already been one U.S. service member killed in 2018 while deployed in support of ongoing counterterrorism operations.
Army Sgt. 1st Class Mihail Golin, 34, a member of the 10th Special Forces Group, died Jan. 1 when his unit came under small arms fire in Nangarhar province in Afghanistan. Four other service members were wounded in that incident.
Thirty-four service members were killed last year while deployed supporting U.S. military operations, according to Department of Defense data.