Nazi hunter Simon Wiesenthal searched for Wallenberg and collected several testimonies. For example, British businessman Greville Wynne, who was imprisoned in the Lubyanka prison in 1962 for his connection to KGB defector Oleg Penkovsky, stated that he had talked to, but could not see the face of, a man who claimed to be a Swedish diplomat. Efim (or Yefim) Moshinsky claims to have seen Wallenberg on Wrangel Island in 1962. An eyewitness asserted that she had seen Wallenberg in the 1960s in a Soviet prison where she worked.