Just to give you an idea, the name of the weapon above translates to "Serb cutter". Instead of gas or bullets, the this was used to slit Serb, Jewish and Gypsy throats at the Croat-run deathcamp called Jasenovac, where the population was more than half women, children and old people. One Ustashi bragged that he was able to slit over 1,000 throats in one night. The Ustashi laughed at the Germans who wasted so much money on gas & bullets when "a knife would do just as well".
The worst of it was that most of the top level of these guys were never punished. The second in command, Andrija Artukovic, lived in the US until the mid 1980's. When he was finally deported, he was a senile old man that was treated more like an "old hero" (under house arrest) than anything else. There is more on the Ustashi and their deathcamp Jasenovac here with quite a collection of photos.
It's worth noting that Jasenovac was the first WWII deathcamp in Europe and the only one not run by Nazi Germany, but by the Croats themselves.