Katyń massacre

The Katyn massacre (Polish: zbrodnia katyńska, mord katyński, "Katyń crime"; Russian: Катынский расстрел Katynskij rasstrel, "Katyn shooting") was a series of mass executions of Polish nationals carried out by the NKVD ("People's Commissariat for Internal Affairs", a Soviet secret police organisation) in April and May 1940. Though the killings took place at several different locations, the massacre is named after the Katyn Forest, where some of the mass graves were first discovered.

The massacre was prompted by NKVD chief Lavrentiy Beria's proposal to execute all captive members of the Polish officer corps, dated 5 March 1940, approved by the Politburo of the Communist Party of the Soviet Union, including its leader, Joseph Stalin. The number of victims is estimated at about 22,000. The victims were executed in the Katyn Forest in Russia, the Kalinin and Kharkiv prisons, and elsewhere. Of the total killed, about 8,000 were officers imprisoned during the 1939 Soviet invasion of Poland, another 6,000 were police officers, with rest Polish intelligentsia that the Soviets deemed to be "intelligence agents, gendarmes, landowners, saboteurs, factory owners, lawyers, officials, and priests".

The government of Nazi Germany announced the discovery of mass graves in the Katyn Forest in 1943. When the London-based Polish government-in-exile asked for an investigation by the International Committee of the Red Cross, Stalin immediately severed diplomatic relations with it. The USSR claimed that the victims had been murdered by the Nazis in 1941 and continued to deny responsibility for the massacres until 1990, when it officially acknowledged and condemned the perpetration of the killings by the NKVD, as well as the subsequent cover-up by the Soviet government.

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