Although the PMO was disbanded in 1921 , Soviet authorities claimed that it continued to exist ; during the Great Purge of 1936-38 , and as early as 1933 , many people of Polish nationality were charged with membership in it , which was illegal , see Polish Operation of the NKVD for the circumstances , and NKVD Order No. 00485 in particular
Polish Operation of the NKVD
Polish Operation of the NKVD
Polish Military Organisation