 Complete the following phrase:  According to Pavel Sudoplatov, NKVD officers Victor Ilyin and Mikhail Maklyarsky conceived Operation Berezino as an extension of Operation Monastyr Operation Monastery 19411944. In 1941, NKVD operative Alexander Demyanov Soviet codename Heyne, wearing a persona of a disgruntled bohemian socialite, established contact with the German resident in Moscow. The NKVD used this opportunity to expose the Abwehr undercover network in the Soviet Union. In December 1941, Demyanov defected to the Germans and showed up at the Abwehr field office in Smolensk. Three months later, he returned to Moscow as a trusted German agent. His apartment became a death trap for scores of genuine German agents, but he retained the trust of his German superiors. In the middle of 1942, Demyanovs control officer Willie Fischer expanded the operation into a strategic level disinformation campaign. For more than two years, Demyanov supplied Reinhard Gehlen, the head of the Oberkommando des Heeres OKH, German Army High Command Fremde Heere Ost Foreign Armies East department with carefully scripted military plans. According to Sudoplatov, the German success in repelling the Soviet 