Incomplete list of Criminal Mobs:
Drug Cartels (Central America)
The Irish Mob primarily operate in North America, but mostly consists of Irish criminals.
Irish Mobs have appeared in games such as Grand Theft Auto IV and Watch Dogs.
The Mafia (Europe, North America)
The Mafia is a term for a group of criminals originating from Italy. The earliest Mafia family originated in the late 19th century.
A popular criminal syndicate in gaming, the Mafia have extensively appeared in games such as the eponymously-titled Mafia series, the Grand Theft Auto series, the Godfather series and several other similar titles.
Outlaw Motorcycle Clubs (North America, Europe)