A U.S. service member died of wounds inflicted by an explosive device outside of the city of Mosul in Iraq, the Pentagon said in a release Saturday.

The release from the U.S.-led coalition gave no other details, and a Pentagon spokesman was unable to elaborate. It is unclear whether the blast was combat-related. Mosul has been the site of heavy fighting since October as Iraqi forces have attempted to rout the Islamic State group from the city.

Saturday’s death, if caused by hostile fire, would be the fifth U.S. combat death in Iraq since the start of the campaign against the Islamic State there in 2014, and the first during the Trump administration. In October, Navy Chief Petty Officer Jason C. Finan was killed by a roadside bomb on the outskirts of Mosul just days after the battle to retake the city began.