Anatoly Yuriyovych Onoprienko (born Ukrainian: Анатолій Юрійович Онопрієнко on July 25, 1959) is a Soviet serial killer. He is also known by the nicknames "The Beast of Ukraine", "The Terminator" and "Citizen O". After police arrested the 37-year-old former forestry student on April 16, 1996, Onoprienko confessed to killing 52 people.