Anti-tank dogs ( sobaki-istrebiteli tankov or protivotankovye sobaki; or Hundeminen, "dog-mines") were dogs taught to carry explosives to tanks, armored vehicles and other military targets. They were intensively trained by the Soviet and Russian military forces between 1930 and 1946, and used from 1941 to 1943, against German tanks in World War II. Initially dogs were trained to leave a timer-detonated bomb and retreat, but this routine was replaced by an impact-detonation procedure which killed the dog in the process. The U.S. military started training anti-tank dogs in 1943 in the same way the Russians used them, but this training exposed several problems and the program was discontinued. Background In 1924, the Revolutionary Military Council of the Union of Soviet Socialist Republics approved the use of dogs for military purposes, which included a wide range of tasks such as rescue, delivery of first aid, communication, tracking mines and people, assisting in combat, transporting food, medicine and injured soldiers on sleds, and destruction of enemy targets. The idea of using dogs as mobile mines was developed in the 1930s, together with the dog-fitting mine design. A specialized dog training school was founded in the Moscow Oblast. Twelve regional schools were opened soon after, three of which trained anti-tank dogs. Training The Workers' and Peasants' Red Army had no dedicated dog trainers in the 1930s, so they resorted to using hunters, police, and even circus trainers. Several leading animal scientists were also involved, in order to help organize a wide-scale training program. German Shepherd Dogs were favored for the program for their physical abilities and ease of training, but other breeds were used as well. In 1935, anti-tank dog units were officially included in the Workers' and Peasants' Red Army. The original idea was for a dog to carry a bomb strapped to its body, and reach a specific static target. The dog would then release the bomb by pulling with its teeth a self-releasing belt and return to the operator. The bomb could then be detonated either by a timer or remote control, though the latter was too rare and expensive at the time to be used. A group of dogs practiced this for six months, but the reports show that no dogs could master the task. They performed generally well on a single target but became confused after the target or location was changed and often returned to the operator