Direct proof of use
The MO-120 RT appears in the 2001 War in Afghanistan through the U.S. Marine Corps M327 Expeditionary Fire Support System, a 120 mm rifled towed mortar package derived from the French MO-120 RT. Marine Corps reporting from February 2011 states that U.S. Marines fired the first Expeditionary Fire Support System rounds in combat operations on January 29, 2011, from Combat Outpost Ouellette in Helmand Province.
The documented unit was F Battery, Battalion Landing Team 3/8, 26th Marine Expeditionary Unit, attached to Regimental Combat Team 2 in support of the International Security Assistance Force. The first reported round was an M1105 illumination projectile fired to light an area occupied by snipers attached to Company I, BLT 3/8.
Sources: 26th MEU EFSS First Combat Rounds, GD-OTS EFSS Ammunition
Timeline
On January 29, 2011, Marines from F Battery, BLT 3/8 fired the first combat rounds from the Expeditionary Fire Support System at Combat Outpost Ouellette. A 26th MEU follow-up account in April 2011 repeated that BLT 3/8's Afghanistan deployment included the first combat use of the EFSS 120 mm mortars.
On March 6, 2011, DVIDS imagery documented a Battery F Marine firing a 120 mm mortar at Combat Outpost Ouellette during Operation Enduring Freedom. On March 30, 2011, a DVIDS video package from Helmand Province described Fox Battery 2/12 using EFSS 120 mm mortars in Afghanistan.
Sources: 26th MEU EFSS First Combat Rounds, 26th MEU BLT 3/8 Deployment Ends, DVIDS Operation Enduring Freedom Mortars, DVIDS EFSS 120mm Mortar Package
Role in Afghanistan
In Afghanistan, the system's documented role was expeditionary indirect fire support for Marine ground operations in Helmand Province. The Marine Corps described EFSS as the third element of its land-based expeditionary fire-support triad alongside the lightweight 155 mm howitzer and HIMARS, with the mortar system able to move by ground vehicle or be transported by MV-22 and CH-53E aircraft.
The January 2011 combat-use account identifies illumination as the first recorded munition role: the M1105 round was used to light terrain around friendly snipers and deter nighttime improvised explosive device emplacement. The GD-OTS EFSS ammunition sheet supports the system background, identifying the M327 as a 120 mm towed rifled mortar and listing high explosive, smoke, illumination, and practice rounds in the EFSS ammunition suite.
The supported catalog side is United States, NATO, and Afghan government forces. The sources used here document U.S. Marine Corps employment of the M327 EFSS/MO-120 RT-derived mortar package; they do not document Taliban or allied militant use of this weapon in the conflict.
Sources: 26th MEU EFSS First Combat Rounds, GD-OTS EFSS Ammunition, DVIDS EFSS 120mm Mortar Package