What do I do about my neighbors? 5 STARS BEST ANSWER?

I live in an okay neighborhood. I mean sure there's gang members here and there but most of them used to hang out at the park but now, my neighbors son and his buddies have started selling drugs across the street! Also, since school got out houses have been broken in to. (My neighbors son and his friends are the only teens in our neighborhood, also the only gang members.) So I took the garbage out like 10 minutes ago and watched a drug deal go down. (A car pulls in to their driveway. The kid comes outside. The kid talks to the driver. Kid goes inside for a few seconds comes back out with a brown paper bag. Driver hands him money. Kid takes it and pats the roof. Kid goes inside and car drives away.) They have drug deals going on all hours! There was a cop that came around the other day but since then nothing. I don't know what I should do cause the drug deal is only for a couple of seconds. Maybe a minute at most!