Cheka, FBI, Gestapo, Interpol, MP, MVD, Mounties, NKVD, OGPU, RCMP, SP, Scotland Yard, bugging, cloak-and-dagger work, constabulary, counterespionage, counterintelligence, county police, electronic surveillance, espial, espionage, following, highway patrol, intelligence, intelligence work, law enforcement agency, military intelligence, military police, observation, police, police force, political police, posse, provincial police, riot police, secret service, security force, shadowing, shore patrol, special police, spying, stakeout, state police, surveillance, tactical police, tailing, trailing, troopers, vigilance committee, vigilantes, wiretap, wiretapping

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