That is how the decision on murdering Polish POWs and political prisoners taken by the Executive Committee of the USSR Communist Party with Joseph Stalin at its head was put into effect. 

According to current estimates, 14,546 POWs - officers of the Polish Army and policemen taken captive by the Soviets in September 1939 - as well as 7,305 political prisoners perished in the Katyn Massacre. They were all shot in the back of their heads by the executioners from NKVD, Stalin’s secret police.

Mass graves of the officers from Kozelsk and Starobelsk were found in Katyn and Kharkiv, whereas those of political prisoners from Ostashkov were located in Mednoye near Tver. In 2000, Polish Military Cemeteries were established there and the murdered captives were properly commemorated. We have much less information on the political prisoners’ fate.

We know the names of roughly half of them; we know of one out of surely several burial places - the one in Bykovnia near Kyiv. All the prisoners executed in the territory of Soviet Ukraine were symbolically commemorated at the military cemetery opened in 2012 in Bykovnia. Yet another likely burial place is in Kuropaty near Minsk; however, in case of Belarus, we do not even hold the list of names of those who perished there.

Relatives of the murdered POWs and political prisoners are the third - indirect - category of victims of the Katyn Massacre. On 13 April 1940, over 60,000 members of the families of those who had been executed in Katyn were deported to North Kazakhstan.

Polish Jews were among the victims of the Katyn murders. Baruch Steinberg, Chief Rabbi of the Polish Army from 1933, is possibly the most well-known of them all. He was an associate of the Piłsudski movement since his youth, a member of the Polish Military Organization and participant of the Defense of Lvov. He was sent to Kozelsk on 11 or 12 April 1940 and subsequently executed in Katyn.

According to the most reliable findings of Benjamin Meirtchak, there were 438 victims of Jewish origin among the murdered captives (231 murdered in Katyn, 188 in Kharkiv and 19 in Tver). The largest group - approximately 5% of Jews - were among the murdered POWs. They were mainly officers of the reserve forces who engaged in professions such as: medical doctors, pharmacists, engineers and lawyers.

We know much less of the murdered political prisoners. There are more than 200 Jews on the list of 3,435 people executed in Ukraine (judging by their first names, first names of their fathers and their surnames). Many were representatives of the social and political elites - barristers, merchants, activists of the Jewish organizations and political parties, as well as reservist officers (for those who had not been taken captive were detained by the NKVD). Some of the victims were people suspected by the NKVD of being agents of pre-war Polish secret police in the Communist movement.

Wiktor Chajes, an independence activist, Deputy Mayor of pre-war Lvov and founder of the Jewish Museum there, was among the civilian victims of the Katyn Massacre. 

Sources:

• Benjamin Meirtchak, "Żydzi – żołnierze wojsk polskich polegli na frontach II wojny światowej", Bellona Publishing House, Warsaw 2001.
• "Śladem zbrodni katyńskiej", ed. Zuzanna Gajowniczek, MSW Publishers, Warsaw 1998.