August 23, 1939 in Moscow was signed the German-Soviet pact. Were divided into spheres of influence in Europe and decided to partition Polish. After a surprise Red Army attack in September 17, 1939 and subsequent days were killed in battle and executed on the spot after being taken captive several thousand Polish officers and soldiers.
Prisoners, which took a Board to Affairs of Prisoners of War and Internees. By the end of October 39 NKVD placed all captured or arrested officers in the camps in Kozelsk and Starobelsk. Amont the prisoners were officers of all grades, who represented all the military professionals. Most of the prisoners were representative of the Polish doctors, lawyers, teachers, civil servants. In the camps there were also many priests of various faiths.
March 5, 1940 Soviet politicans decided to murder more than 14 000 prisoners living in Kozielsk, Ostaszkow and Starobelsk. Under the same decision also killed 7 thousands of Polish nationality peoples, who are in NKVD prison.
April 3, 1940 - from Kozielsk were taken first group of prisoners. Over the next few days departed from the camp transports including more people. Polish officers were transported by train to the station located near Smolensk, and from there take them to NKVD resort. They were murdered in the back of the head shot in Katyn forest. Prisoners of Ostashkov killed at the NKVD headquarters in Kalinin, and buried in Miednoye. Prisoners located in Starobielsk murdered in Kharkov.