Black Doggerel

Whether the kid is trying deliberately to be threatening or not, if he's old enough to be in the street at all I'd say he's old enough to understand and respect the meaning of the word "NO." If he doesn't, that's his parents' fault and certainly they know how he behaves; the fact that he's allowed out to do this is plain and simple rudeness -- or perhaps neglect -- on their part. I'd certainly speak to the police about your options.