A rifleman serving with Delta Company, 1st Battalion, 1st Marine Regiment, is alerted when he sees enemy activity from a nearby rooftop during an Urban Leaders Course training scenario at a military operations on urban terrain facility here, Sept. 19, 2013. The Marines provided around-the-clock security for a building at the facility and then assaulted a nearby building with armed role-players, played by fellow Marines, who were threatening overall security. The Marines, both friendly and enemy forces, used simunition rounds – simulated ammunition that contains paint to mark upon impact. Delta Co. focused on laws of land warfare, urban warfare and counterinsurgency tactics during the training.