Cheka (ЧК – чрезвыча́йная коми́ссия chrezvychaynaya komissiya, Emergency Committee, Russian pronunciation: [tɕɪˈka]) was the first of a succession of Soviet state security organizations. It was created on December 20, 1917, after a decree issued by Vladimir Lenin, and was subsequently led by Felix Dzerzhinsky, a Polish aristocrat turned communist.