Oleg Vladimirovich Penkovsky (Russian: Оле́г Влади́мирович Пенько́вский; 23 April 1919 – 16 May 1963), codenamed HERO, was a Soviet military intelligence (GRU) colonel during the late 1950s and early 1960s. Penkovsky is known for informing the United Kingdom about the Soviet emplacement of missiles in Cuba, thus providing both the UK and the United States with the precise knowledge necessary to address rapidly developing military tensions with the Soviet Union.