of some insurgent groups, according to a report by the MGB of the Ukrainian SSR, the "liquidation of armed units and OUN underground was accomplished by the beginning of 1956". NKVD units dressed as UPA fighters are known to have committed atrocities against the civilian population in order to discredit the UPA. Among these NKVD units were those composed of former UPA fighters working for the NKVD. The Security Service of Ukraine (SBU) recently published information that about 150 such special groups consisting of 1,800 people operated until 1954. Prominent people killed by UPA insurgents during the anti-Soviet struggle included Metropolitan Oleksiy (Hromadsky) of the Ukrainian Autonomous Orthodox Church, killed while travelling in a German convoy, and pro-Soviet writer Yaroslav Halan. In 1951 CIA covert operations chief Frank Wisner estimated that some 35,000 Soviet police troops and Communist party cadres had been eliminated by guerrillas affiliated with the Ukrainian Insurgent Army in the period after the end of World War II. Official Soviet figures for the losses inflicted by all types of Ukrainian nationalists during the period 1944–1953 referred to 30,676 persons; amongst them were 687 NKGB-MGB personnel, 1,864 NKVD-MVD personnel, 3,199 Soviet Army, Border Guards, and NKVD-MVD troops, 241 communist party leaders, 205 komsomol leaders and 2,590 members of self-defence units. According to Soviet data, the remaining losses were among civilians, including 15,355 peasants and kolkhozniks. Soviet archives state that between February 1944 and January 1946 the Soviet forces conducted 39,778 operations against the UPA, during which they killed a total of 103,313, captured a total of 8,370 OUN members and captured a total of 15,959 active insurgents. Many UPA members were imprisoned in the Gulag. They actively participated in Gulag uprisings (Kengir uprising, Norilsk uprising, Vorkuta uprising). Soviet infiltration In 1944–1945 the NKVD carried out 26,693 operations against the Ukrainian underground. These resulted in the deaths of 22,474 Ukrainian soldiers and the capture of 62,142 prisoners. During this time the NKVD formed special groups known as spetshrupy made up of former Soviet partisans. The goal of these groups was to discredit and disorganize the OUN and UPA. In August 1944, Sydir Kovpak was placed under NKVD authority. Posing as Ukrainian insurgents, these special formations used violence against the civilian population of Western Ukraine. In June 1945 there were 156 such special groups with 1,783 members. From December 1945 to 1946, 15,562 operations were carried out in which 4,200