Trobec's modus operandi consisted of bringing out unfamiliar women to his homestead, where he raped and strangled them, severely beating two of his victims until they were bleeding. After killing them, he would shove their corpses into a masonry oven and then set them alight with gasoline and firewood, later throwing out the ashes and remaining human bones in a wooden urn or a nearby septic tank. The victims' personal items and documents were either also burned, or brought to the homestead in Spodnja Bela. Investigators were unable to determine the exact reason why Trobec did not kill every woman he brought with him, but some speculated that he only targeted victims with health problems, as two of his victims suffered from epilepsy.
