A contingent of roughly 400 Marines are headed home from Syria after three months of providing fire support to U.S.-backed Kurdish and Syrian Arab Forces who battled Islamic State fighters in the militant group’s former capital.

The Camp Lejeune, North Carolina-based Marines and sailors were part of an artillery detachment with 1st Battalion, 10th Marine Regiment, and arrived in Syria in September, where they proceeded to shell ISIS with such intensity that they burned out not one but two M777 155mm howitzer barrels, according to Marine Corps Times.

The Nov. 30 announcement that the recently arrived artillery detachment is on its way home was cited as a sign of success following the Oct. 20 ouster of ISIS from Raqqa.

“The departure of these outstanding Marines is a sign of real progress in the region,” Brig. Gen. Jonathan Braga, director of operations in Iraq and Syria, said. “We’re drawing down combat forces where it makes sense, but still continuing our efforts to help Syrian and Iraqi partners maintain security.”

Marine Corps artillery units, especially those deployed from a Marine Expeditionary Unit — an all-in-one Marine Corps task force able to bring troops, indirect fire, and air support to bear — provide U.S. allies a long and devastating reach.

“With a 155mm artillery battery in the fight, their mission was to deny and disrupt ISIS from gaining ground or moving from their defensive positions,” Lt. Col. Jon O’Gorman, chief of fires for Combined Joint Task Force Operation Inherent Resolve, said of the Marines from 1/10. “These Marines rained relentless and highly accurate firepower on the enemy.”

The employment of Marine artillery batteries in the fight against ISIS over the last year-and-a-half is one of the few instances where conventional ground-combat personnel — rather than special operations forces in Syria or Iraq — have engaged the militants.

Photo by Sgt. Matthew Callahan
A U.S. Marine fires an M777-A2 Howitzer in the early morning in Syria, June 3, 2017.

Conventional forces or not, information surrounding the employment of these artillery batteries, their time on the ground, and specifics on their mission there, are often vague.

The Marines and sailors with 1/10 replaced an artillery battery reportedly attached to the 24th Marine Expeditionary Unit. Prior to the all-weather fire mission conducted by the 24th MEU’s artillery Marines in June, troops with the 11th MEU fired upwards of 4,500 rounds at Islamic State targets in and around Raqqa, Task & Purpose previously reported.

Related: 7 Badass Photos Of Marines Shelling The Crap Out Of ISIS In Syria »

For two and a half months in 2016, artillerymen with Echo Battery, 2nd Battalion, 10th Marines provided fire support to Iraqi security forces as they advanced on Mosul, which was liberated from ISIS in July. The first conventional American ground troops to set up a semi-permanent fire base, the Marines stood up a small outpost March 16 and were rocketed by Islamic State militants on numerous occasions. The news that Marines were manning a fixed position and engaged in fire missions against ISIS only came to light following a rocket attack that resulted in the death of Staff Sgt. Louis Cardin, the Washington Post reported March 22, 2016.

Much of what is known about the challenges facing these Marine gun crews is still unclear, and often remains so until the information is released following a tragedy, or an award ceremony. As for what we know for sure: The Marines with 1/10 are expected to head back home, and with Raqqa no longer under ISIS control, the arty unit’s replacements have been “called off,” according to the Operation Inherent Resolve statement.

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