In its 1938 ' Polish Operation ' committed wholly inside Soviet Russia , the NKVD arrested 143,810 .
In its 1938 ' Polish Operation ' committed wholly inside Soviet Russia , the NKVD executed 111,091 , mostly Poles .
In its 1938 ' Polish Operation ' committed wholly inside Soviet Russia , the NKVD arrested 143,810 and executed 111,091 , mostly Poles .