In the latter days of the USSR and red bloc eastern European nations OMON units were more like the old terror Cheka.
Polish friends who emmigrated during the upheavals said they acted as agent provocateurs as well as targeting opposition leaders for severe back alley beat downs as well as outright assassinations. Steroid and meth use was administered by OMON command. I was told that more than a few had to be taken down by their own teams for running totally out of controll.
Agent provocateurs is interesting in light of the 2920 summer riots and the J 6 riot that had some many agents provocateur, one of which fled to Belarus.