The K-9 plays an important role in law enforcement in various missions with specialized training and unique abilities. They were first used in Belgium in 1899, made their way to the U.S. by 1907 and by 2024 there was an estimated 50,000. These canines are selected for their intelligence, loyalty, exceptional sense of smell and natural aggression. Their sharp olfactory abilities allow them to detect substances at incredibly low concentrations searching for explosives, drugs, and missing persons. Their role expanded to rising security concerns, especially in terrorism. Breeds most often chosen are Belgian sheepdogs, German Shepherds, Malinois and hounds.