The Katyn massacre was actually a series of mass executions performed by Soviet forces against Polish POW, specifically members of the Officers corps. About 22.000 officers were killed.
It happened in April and May of 1940, some months after the occupation of part of Poland by the Red Army (September 1939).
The monument is located in a park in a central area of Wroclaw, near the Panorama museum. It has a symbolic shape, with an angel holding a sword and what seems to be a supplicant.
The massacre of Katyn has been an issue in the relationship between modern Poland and Russia, as Moscow refuses to recognize the dark events of that Spring of 1940.
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