Petro Grigorenko or Petro Hryhorovych Hryhorenko (Ukrainian: Петро́ Григо́рович Григоре́нко, 16 October [O.S. 3 October] 1907 – 21 February 1987) was a high-ranking Soviet Army commander of Ukrainian descent, who in his fifties became a dissident and a writer, one of the founders of the human rights movement in the Soviet Union. For 16 years, he was a professor of cybernetics at the Frunze Military Academy and chairman of its cybernetic section before joining the ranks of the early dissidents. In the mid-1970s Grigorenko helped to found the Moscow Helsinki Group and the Ukrainian Helsinki Group, before leaving the USSR for medical treatment in the United States. The Soviet government barred his return, and he never again returned to the Soviet Union. In the words of Joseph Alsop, Grigorenko publicly denounced the "totalitarianism that hides behind the mask of so-called Soviet democracy." Source: Wikipedia (en)