EntityQ3884022· pop 9· linked from 722 articlesOperation UnderworldSign in to saveUS intelligence operation, involving cooperation with mobstersConnectionsAmerican MafiaEntityBenito MussoliniPersonInternational Standard Book NumberEntityNazismEntityAxis PowersEntityAllies of World War IIEntityHudson RiverEntityAttack on Pearl HarborConceptFederal Government of the United StatesEntitydeportationEntityBattle of the AtlanticEntityAllied invasion of SicilyEntityLucky LucianoEntitySicilian MafiaEntityU-boatEntityOmertàEntityfeudEntityThomas E. DeweyEntityNormandieEntityMeyer LanskyEntityCategoriesAmerican Mafia eventsJewish-American organized crime eventsMilitary history of New York (state)Office of Naval IntelligenceOperation UnderworldUnited States home front during World War II