Marines with Weapons Company, Battalion Landing Team 2nd Battalion, 5th Marines, 31st Marine Expeditionary Unit, sweep buildings for enemy forces during urban combat training here, Feb 8. The Marines utilized 5.56mm Special Effects Small Arms Marking System (SESAMS) rounds and a Military Operations on Urban Terrain facility to simulate actual combat. The 31st MEU is the Marine Corps’ force in readiness in the Asia-Pacific region and is the only continuously forward-deployed MEU. - Marines with Weapons Company, Battalion Landing Team 2nd Battalion, 5th Marines, 31st Marine Expeditionary Unit, sweep buildings for enemy forces during urban combat training here, Feb 8. The Marines utilized 5.56mm Special Effects Small Arms Marking System (SESAMS) rounds and a Military Operations on Urban Terrain facility to simulate actual combat. The 31st MEU is the Marine Corps’ force in readiness in the Asia-Pacific region and is the only continuously forward-deployed MEU.