the form of troop security used when troops are halted in an area threatened by a possible enemy attack by land. Security at the halt is usually detailed by a regiment or a separate unit in order to prevent the penetration of enemy reconnaissance into the area occupied by the halted troops, to warn the troops in sufficient time of an enemy attack, and to ensure an organized deployment and entry into battle. Security organs include outpost detachments, outpost support elements, outguards, patrols, listening posts, and observation posts. A sentry detachment, ranging in strength from a reinforced company to a reinforced battalion, is usually dispatched to cover the most important axis. Security in a 5- to 10-km belt is organized by detaching outpost support elements (in strengths up to reinforced platoons), which organize security in belts of up to 2 km. Such support elements dispatch outguards (in squad strength or less), patrols, listening posts, and observation posts.