tactics include directing artillery or mortar fire onto suspected sniper positions, the use of smoke screens, placing tripwire-operated munitions, mines, or other booby-traps near suspected sniper positions. Even dummy trip-wires can be placed to hamper sniper movement. If anti-personnel mines are unavailable, it is possible to improvise booby-traps by connecting trip-wires to hand grenades, smoke grenades or flares. Though these may not kill a sniper, they will reveal their location. Booby-trap devices can be placed near likely sniper hides, or along the probable routes to and from positions. Knowledge of sniper field-craft will assist in this task. The use of canine units had been very successful, especially during the Vietnam War. Irregular and asymmetric warfare The use of sniping (in the sense of shooting at relatively long range from a concealed position) to murder came to public attention in a number of sensational U.S. criminal cases, including the Austin sniper incident of 1966 (Charles Whitman), the John F. Kennedy assassination (Lee Harvey Oswald), and the Beltway sniper attacks of late 2002 (Lee Boyd Malvo). However, these incidents usually do not involve the range or skill of military snipers; in all three cases the perpetrators had U.S. military training, but in other specialties. News reports will often (inaccurately) use the term sniper to describe anyone shooting with a rifle at another person. Sniping has been used in asymmetric warfare situations, for example in the Northern Ireland Troubles, where in 1972, the bloodiest year of the conflict, the majority of the soldiers killed were shot by concealed IRA riflemen. There were some instances in the early 1990s of British soldiers and RUC personnel being shot with .50 caliber Barrett rifles by sniper teams collectively known as the South Armagh sniper. The sniper is particularly suited to combat environments where one side is at a disadvantage. A careful sniping strategy can use a few individuals and resources to thwart the movement or other progress of a much better equipped or larger force. Sniping enables a few persons to instil terror in a much larger regular force – regardless of the size of the force the snipers are attached to. It is widely accepted that sniping, while effective in specific instances, is much more effective as a broadly deployed psychological attack or as a force-multiplier. Snipers are less likely to be treated mercifully than non-snipers if captured by the enemy. The rationale for this