Wallenberg and his driver, Vilmos Langfelder, left Budapest for a meeting with the Russian Commander, Marshal Malinovsky, in Debrecen, Hungary. On the way, he and his driver were taken into "protective custody" by the Soviet NKVD, the secret police later known as the KGB. The Soviet deputy foreign minister, Vladimir Dekanosov, notified the Swedish Ambassador in Moscow that Wallenberg was in Russian hands; "The Russian military authorities have taken measures to protect Raoul Wallenberg and his belongings," said the note.
Bernard Rensinghoff communicates with Raoul Wallenberg in Lefortovo Prison in Moscow. Rensinghoff was in cell 161 while Wallenberg and his cell mate Willi Roedel were in Cell 203. They communicated by knocking on the wall. Wallenberg told Rensinghoff of his work in Budapest and his capture. He gave his address as Stockholm. A great deal of time was spent by Rensinghoff helping Wallenberg write a memorandum in French to Stalin. Wallenberg, pointing to his diplomatic status, requested that he be given the opportunity to contact the Swedish Legation in Moscow. Sometime later, Wallenberg received a message acknowledging that his petition had been received. At Wallenberg's interrogation (the first in two years since his arrest), the KGB commissar told him that his case was quite clear. He was a "political" case. If he considered himself innocent, the onus was on him to prove it. Their proof that Wallenberg was guilty was based on the fact that the Swedish government and the legation in Moscow had done nothing on Wallenberg's behalf. Wallenberg requested that he be able to contact the Legation or the Red Cross - at least to write to them. This request was denied on the basis that they had long since forgotten him and didn't care about him. Wallenberg was also told that, for political reasons, he would never be convicted. After tapping a message about this interrogation, Wallenberg's final message was, "We are being taken away".
More than a year after Wallenberg’s report death, at Corpus II hospital block of Vladimir Prison, a Swiss prisoner named Brugger "talked" by tapping code on his cell wall. "The Swede in the next cell identified himself as Wallenberg, First Secretary Swedish Legation, Budapest, 1945." He asked Brugger to contact any Swedish embassy or consulate and report this information, if he ever was released.
Abraham Kalinski saw Wallenberg several times exercising in the prison yard with other prisoners.
Abraham Kalinski reports having seen Wallenberg during a prisoner transfer to Vladimir Prison. They were on the same train.
American student from the University of Pennsylvania arrested for espionage while touring the Soviet Union in the summer of 1961, Marvin Makinen, is imprisoned at Vladimir Prison for twenty months. While at Vladimir, Makinen's cell mate is a Latvian prisoner, Kruminsh, who had also been a cell mate of Gary Powers. Upon arriving at a labor camp in August 1963, Makinen was questioned about his former cell mates by an older political prisoner. When Makinen mentioned Kruminsh's name, the older prisoner was disgusted. "Kruminsh, that son of a bitch. He got to sit with all the foreign prisoners", the man grumbled. "He got to sit with Powers, he got to sit with you, Marvin, and he got to sit with the Swedish prisoner Vandenberg". It wasn't the first time Makinen had heard about a Swedish prisoner. Both an earlier cell mate and even Kruminsh had mentioned that a Swedish prisoner had been held in Vladimir Prison. A year after his release in October of 1963, Makinen was invited to the Swedish embassy in Washington to recount how he learned about the Swedish prisoner. This time, he was informed that Vandenberg had been a Swedish diplomat in Budapest who had helped Jews escape the Nazis, and that the man had not been heard from since Soviet troops moved into Budapest in 1945 That man was Raoul Wallenberg.
Swedish Prime Minister, Tage Erlander, turns down an offer from the Soviet Union to trade Raoul Wallenberg for Soviet spy Stig Wennerstrom then in prison in Sweden. The offer was made by the Soviet KGB and was first made to Swedish authorities in the autumn of 1965. This offer was confirmed in 1991 by the participants in this offer, Otto Danielsson and Carl Persson of the Swedish Government and the go-between with the Soviets, Carl Gustav Svingel, who now lives in Berlin. The seriousness of this proposed spy swap was also confirmed by the late Swedish Prime Minister, Tage Erlander. When Svingel asked his Soviet counterpart if Wallenberg lived, he was informed that "We usually don't negotiate about dead people." Col. Stig Wennerstrom was sentenced to life in prison on June 12, 1964 and was an important spy for the Soviet Union. According to Danielsson, the Swedish Government felt that if they gave up Wennerstrom to the Soviets, who then gave him a good pension, then he would be a heavy argument at the recruitment of new spies. As Wallenberg was not a spy, the Swedish Government was not going to barter for him. While the Cabinet of Sweden decided against the swap on the grounds that they would not deal with the KGB, the fact that it was proposed by Soviet agents clearly establishes THAT WALLENBERG WAS ALIVE AFTER THE SOVIET SUPPOSED DATE OF DEATH IN 1947. The KGB offer was also confirmed in May 1992 by Finnish and by German (following the reunification of Germany) sources. The Swedish press released the news of this release effort in April 1991.
A young Soviet Jewish immigrant to Israel, who wished to remain anonymous because of his family in the Soviet Union, tells of a party at the Moscow home of a senior KGB officer on May Day 1978: "Much vodka was drunk and the younger men at the party began to speak of dissidents and the rough time they must have in prison. The KGB officer burst out and said, "Don't you believe it; things aren't so tough nowadays as they used to be. Why I have a Swede under my charge in Lubianka who's been inside for over 30 years!" The young Russian heard of Wallenberg in Israel for the first time and then went to the Swedish Embassy in Israel where he filed a report.
Raoul Wallenberg's sister, Nina Lagergren, his brother, Guy von Dardel, Ambassador Per Anger and Sonja Sonnenfeld from the Swedish Raoul Wallenberg Committee visited Moscow at the invitation of the USSR Ministry of Foreign Affairs. This was their first visit to the USSR to discuss the fate of Raoul Wallenberg with officials since he disappeared. During the meeting, they were given the following items connected with Raoul Wallenberg's case: A report on his purported death on July 17, 1947 and his cremation written by Dr. A. Smoltsov (then head of medical services at the KGB Lubianka Prison), a diplomatic passport, two identification documents, two food ration cards, notebooks, a sum of money in American , Swiss, Swedish and Hungarian currency, and a number of personal items. The KGB claimed to have discovered these articles "by accident... During this meeting, Nina Lagergren was given a piece of paper to sign. She was told by the KGB that it was a receipt for Raoul's belongings. Mrs. Lagergren does not speak or read Russian, but Sonja Sonnenfeld does. Sonja looked at the paper and was shocked. It was not a receipt at all. Instead it was a statement saying that Raoul Wallenberg's family agrees that the Soviet Union has done all they can on the Wallenberg case and that the family agrees that the case is closed. (This was told by Sonla Sonnenfeld at the annual meeting of the Raoul Wallenberg Committee of the U.S.) Needless to say, Mrs. Lagergren did not sign the paper.
During a trip to Stockholm, Simone Lucki, a Belgian attorney, gave a copy of a photograph to Diane Blake of The Raoul Wallenberg Committee of the United States. The photograph, dating from 1955, was given to Ms. Lucki by Natalia Scinkarenko, a Ukranian who was imprisoned in a Communist prison. She identifies one man in the photo as Wallenberg. Around the beginning of 1955 she and others heard from a German prisoner that he had encountered Raoul Wallenberg in another prison. Later that year, the prisoners were treated to a concert in which other men prisoners in Baltic folk costumes played and sang. One was identified to her as "Valenbergis". When she was released in 1961, she received a photograph of the group from a priest who was also in it and she has kept it all these years. She heard about Wallenberg again in 1989 when the Soviets permitted information about him on the radio. Not until she moved to Brussels did she reveal the photo. The photograph was sent by the Raoul Wallenberg Committee of the United States to Mr. Horace Heafner, an age progression specialist, from the National Center for Missing and Exploited Children in Arlington, Virginia to provide a comparison between the face of Raoul Wallenberg (31 years old) and the face of the person in the picture. While Mr. Heafner felt that there were many similarities between the prison photograph and the picture of Raoul Wallenberg at 31 years of age, the quality of the prison photograph made it impossible for the identification to be conclusive.