Marines with Combat Logistics Battalion 26, 26th Marine Expeditionary Unit, rush injured Marines on litters to an MV-22B Osprey during a mass casualty training exercise at Fort Pickett, Va., Sept. 14. A mass casualty is defined as any number of casualties produced in a relatively short period of time that overwhelms the emergency medical services and logistical support. This training is part of the 26th MEU?s pre-deployment training program. CLB-26 is one of the three reinforcements of 26th MEU, which is slated to deploy in 2013. - Marines with Combat Logistics Battalion 26, 26th Marine Expeditionary Unit, rush injured Marines on litters to an MV-22B Osprey during a mass casualty training exercise at Fort Pickett, Va., Sept. 14. A mass casualty is defined as any number of casualties produced in a relatively short period of time that overwhelms the emergency medical services and logistical support. This training is part of the 26th MEU?s pre-deployment training program. CLB-26 is one of the three reinforcements of 26th MEU, which is slated to deploy in 2013.