In military tactics, the kill zone, also known as killing zone, is an area entirely covered by defensive fire, an element of ambush within which an approaching enemy force is trapped and destroyed. The objective of the defensive force is to quickly kill or capture all enemy soldiers inside the kill zone. The trapped soldiers may respond by counterattacking.
The term is used in a similar but non-lethal fashion in paintball and airsoft tactics.
The kill zone is an element of point ambush in which a military unit targets a single area with defensive fire such as mines, demolitions and guns. The kill zone may be bordered by obstacles, traps or indirect fire (artillery or mortars) to keep the enemy from escaping. In an area ambush, related multiple kill zones will be covered by multiple defensive units. The weapons of the kill zone are not fired until the majority of the enemy unit is within the kill zone, ideally all of the targeted unit. Defensive fire is initiated by the defensive unit leader who orders the most devastating weapons to be engaged, followed immediately by other weapons. The initial attack may be remote-controlled charges such as Claymore mines or other explosives. The ambushed unit may be prevented from advancing or retreating by explosions at the front and rear of their column. Machine gun and small arms fire may be augmented by indirect fire. Ideally, the action is completed so quickly that the enemy force has no time to report the engagement. A successful ambush may result in a patrol in the kill zone being destroyed in seconds. The ambush of a kill zone carries high risk in that forces not in the zone may maneuver around the flanks of the attackers, limiting their escape. Nearby forces may also come to the assistance of those caught in the attack. For this reason, a well-executed attack may be over in under a minute and rarely extends beyond a few minutes.
A military unit that finds itself suddenly under fire in an enemy kill zone must immediately take action against the ambushers. Such action may include soldiers assuming a prone position to minimize themselves as targets. Prone soldiers will return fire toward the ambushers. Other responses may include the targeted soldiers immediately assaulting suspected defensive positions. Soldiers outside of the kill zone may direct suppressive fire at the ambushers in support of the assault, and they may advance upon the flanks of the ambushers.
Vehicles in the kill zone will likely attempt to leave it, while vehicle gunners fire toward the ambushers. Disabled vehicles may create cover for ambushed soldiers. Soldiers able to leave their disabled vehicles are expected to join the assault against the ambushers.
The kill zone should isolate and trap the enemy. The selection of a likely kill zone involves evaluating the terrain and making up for any inadequacies. First and foremost, the kill zone must be where the enemy is expected to travel, or where the enemy can be attracted with "bait". If the potential kill zone terrain restricts vehicle movement to one vehicle width at a time, then a suddenly disabled vehicle will help to isolate the enemy. Terrain that keeps the enemy from moving out of the kill zone is useful for isolation, otherwise the ambushers will wish to place obstacles or munitions at the borders of the selected area. Especially important is separation between the enemy and the ambushing units, to prevent a counterattack.
Military units on the move are vulnerable to ambush. To avoid the kill zone, a patrol may "fan out" and travel with elements spread out left and right, rather than staying solely on a road or track. Soldiers who take point must keep an eye out for signs of a kill zone, such as disturbed ground, obstacles and restrictive terrain. Night vision and thermal imaging equipment may help to discover hidden weapons, or enemy soldiers under cover.
The term "kill zone" is used in paintball tactics to designate an area that is heavily defended by enemy paintball players. Advancing players may know the location of the potential kill zone but be uncertain whether it is well-defended. Responses vary to being caught in a paintball kill zone. If the kill zone is too large and the enemy forces relatively far away, the ambushed players often retreat to cover. If the kill zone is small, the ambushed players are likely to charge forward and assault the defensive players. Fellow players who are not caught in the kill zone are likely to attack the flanks of the defensive players.