Hanusiak claimed that Soviet newspapers and archives had provided the names during his visit to Kiev in 1974; however, INS suspected that Hanusiak, a member of the Communist Party USA, had received the list from the KGB. It chose to investigate the names as leads. Hanusiak claimed that Demjanjuk had been a guard at Sobibor concentration and death camp. INS quickly discovered that Demjanjuk had listed his place of domicile from 1937-1943 as Sobibor on his US visa application of 1951. This was considered circumstantial corroboration of Hansiuk's claims, but its agents were unable to find witnesses in the US who could identify Demjanjuk.