Well, well, Officer, necromancers have always existed, since ancient times, just like prostitutes. Of course, it is not known for sure whether their activities were of any use, and it would be even more foolish to imagine uprisings of the undead or something similar. But it is possible that these guys knew something – how to drive a person crazy, how to poison someone, or something else. For which they were naturally burned. And not always was the attitude towards them bad – for example, towards the same shamans, who, by summoning spirits, also engage in a kind of necrophilia.