Rapper A$AP Rocky -- Arrested After Brawl with Photogs

Rapper A$AP Rocky was taken into NYPD custody tonight after he allegedly put the smackdown on 2 guys who took pics of him ... TMZ has learned.

According to law enforcement sources ... A$AP Rocky, real name Rakim Mayers, had gotten into a verbal dispute with someone in downtown Manhattan, when 2 civilians started snapping photos of the incident.

We're told A$AP and a friend quickly turned their attention to the amateur photogs ... and a full-fledged fight erupted. Our sources say the two victims suffered cuts and bruises with one requiring treatment at a hospital.

We're told responding officers arrested AR ... and he's expected to be booked for attempted robbery. It's unclear, at this point, what he's accused of trying to pilfer.