I'd say the Ndrangheta is the most powerful crime group in all of Europe. They are everywhere. In Belgium there are a lot of Ndrangheta members in (relatively small) villages with a substantial Italian population. In one village particularly there is a pretty powerful clan at work. They are often in a cafe a friend of mine owns.
Oh yeah, and they completely piss on the myth that mobsters dress in sharp suits and solely drive in shiny Lamborghini's. These people just look like thugs They are ( without condoning them) actually pretty friendly, but still do some twisted stuff of course