The Volhynian massacre - anti-Polish ethnic cleansings conducted by Ukrainian nationalists culminated in the summer of 1943. The massacres took place within Poland's borders as of the outbreak of the Second World War, and not only in Volhynia, but also in other areas with a mixed Polish-Ukrainian population, especially the Lvov, Tarnopol, and Stanisławów voivodeships (that is, in Eastern Galicia), as well as in some districts bordering on Volhynia.
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