A police dog, often referred to in North America as a "K-9" (which is a homophone of canine), is a dog that is trained specifically to assist police and other law-enforcement personnel in their work, such as searching for drugs and explosives, searching for lost people, looking for crime scene evidence, and protecting their handlers. Police dogs must remember several hand and verbal commands. The most commonly used breed is the German Shepherd. In many jurisdictions, the intentional injuring or killing of a police dog is a felony, Many dogs were used to locate mines. They did not prove to be very effective under combat conditions. Marine mine detecting dogs were trained using bare electric wires beneath the ground surface. The wires shocked the dogs, teaching them that danger lurked under.
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