While the police are unsure of exactly what's happening, official speculation is that, because last year a drug lord was gunned down, it has created a power vacuum, and there is now an organized crime battle over the turf. The police call the fire bombs amateurish, so they suspect it is street gangs working for either the bikers (bikers are really big here) or the mob as deniable assets (might be inter-mafia conflicts). In any case, the café owners aren't talking.
So yeah, that stuff from the sourcebooks? Totally bang on

P.S. I'd like to some articles, but the best ones are in french only.