Genocide in Pozsonyligetfalu/Petržalka

Who and why did put a bullet through the heads of Hungarian and German infants and children, in addition to exterminating whole families in the near of Přerov (Prerau), Moravia on June 18th 1945? For what reason were the bodies of murdered women and children cremated in the crematory of Olomouc (Olmütz), Moravia, after being disinterred by army units two years after the mass massacre? Why did the Czech historian who had detected the fate of massacred Hungarian and German families not get any appreciation or honor from Budapest? And what happened to those 90 Hungarian soldiers (levente) who were handed over to Slovak army soldiers by Soviet forces occupying Austria?