In WWII, they shot, and set fire to their own neighbors, fellow countryman, and destroyed villages, while serving in Hitler’s Wehrmacht and Waffen-SS units. Records show approximately 250,000 men who identified as Ukrainian, served under Hitler.
Then there were Bandera's boys, who murdered over 100,000 Poles.
To be fair, the Germans gave them two choices, work for us and get food rations, or don't work for us and get no food ration and probably be viewed as a partisan..