The U.S. is sending a detachment of Marines to Iraq following a deadly attack on a coalition base in northern Iraq that left one Marine dead and eight more injured.

The Marines and sailors headed to Iraq are with come from the 26th Marine Expeditionary Unit, according to the U.S. task force running the war against the Islamic State group announced on Sunday. The detachment will augment Marines and sailors already fighting ISIS, officials said Sundaythe Islamic State.

It is not immediately clear how many Marines and sailors from the 26th MEU are deploying to Iraq or whether they are replacing any of the Marines injured in Saturday's rocket attack.

The 26th MEU is currently deployed to the 5th Fleet area of operations with the Kearsarge Amphibious Ready Group. The more than 4,000 Marines and sailors with the blue-green team have been deployed since October. On March 8, an AV-8B Harrier caught fire while preparing to take off from the amphibious assault ship Kearsarge while the 26th MEU was in the Persian Gulf. The Harrier was assigned to Medium Tiltrotor Squadron 162 (Reinforced).

News of the Marines headed to Iraq deployment comes one day after Staff Sgt. Louis F. Cardin, who was deployed with the 26th MEUalso of the 26th MEU, was killed by a rocket attack on a coalition fire base near Makhmur, Iraq. ISIS which is near where the Islamic State launched has launched mustard gas attacks in that area.  and where Kurdish Ppeshmerga fighters also stopped an attempted attack there in November when the terror group tried to use Islamic State attack using mortar rounds filled with chlorine gas in November.

Makhmur is also where the Nineveh Operations Center is located. It is a primary base from which the U.S. can support Iraqi forces when they eventually try to retake Mosul, which fell to the Islamic State in June 2014. Iraqi military leaders plan to deploy about 4,500 troops to the area for the upcoming operation.

Hundreds of Marines have been quietly deploying to Iraq over the past 16 months to assist Iraqis fighting to retake territory from ISIS militants.