WASHINGTON — The Pentagon will consider opening more small military outposts that would provide artillery support and other aid to Iraqi forces as they prepare to retake the northern city of Mosul from Islamic State militants, a senior military officer on the Joint Staff said Wednesday.

Rear. Adm. Andrew Lewis, the vice director for operations, said there may be situations where the U.S. would either open a base or reopen one that was used in the earlier Iraq war. Those outposts, he said, would be behind the front lines, and would be used the way U.S. Marines are operating out of what has been known as Fire Base Bell, outside Makhmour.

Last month fewer than 200 Marines set up the outpost and provided targeting assistance and artillery fire for the Iraqis. It was the first time such a base had been established by the U.S. since it returned forces to Iraq in 2014.

Initially military officials said the base was set up purely to provide force protection for Iraqi forces and U.S. advisers at the nearby Iraqi base in Makhmour.

But soon after, the Marines were firing illumination rounds to help the Iraqi forces locate IS fighters, and also firing artillery rounds in support of the operation, as Iraqi troops took control of several villages on the outskirts of Makhmour, southeast of Mosul. The Marine remained well behind the front lines.

Lewis said that setting up another similar base as the Iraqi forces move toward Mosul is “dependent on what’s happening on the ground” and in the military campaign.

“As Iraqi security forces progress toward isolating Mosul, there may be a situation in which there is another base,” he said, adding that it could be a former U.S. outpost and would be used to provide artillery fire from behind the front lines.

“Their mission is to provide fires and support of Iraqi forces, just like we do with airplanes, just it’s surface-to-surface fires (versus) air-to-surface fires,” he said. “Same concept, very accurate.”

He added that additional security measures have been put in place at Fire Base Bell since an attack on the outpost several weeks ago.

Marine Staff Sgt. Louis F. Cardin of Temecula, California, was killed by rocket fire in that attack. The Marines at the fire base are part of the 26th Marine Expeditionary Unit, which has been based on the USS Kearsarge, an amphibious assault ship that has been deployed in the region.

Pentagon officials have said they are on a temporary, short-term deployment into Iraq.

During the years of the Iraq war, U.S. forces set up a number of small forward operating bases or combat outposts around the country.

Lewis also noted there has been a recent name change for Fire Base Bell. It’s unclear why the military changed names, but the new name — the Karasoar Counterfire Complex — reflects the Iraqi location and appears to focus more on its security mission rather than a combat role.