Please Help is this guy going to ruin my life?

I've been dating this guy for about a year he's apart of a gang he picks fights with other guys when we are out together in public he gets drunk starts to act really loud.He starts stuff with people for no reason.He's very dangerous he just recently put hid hands on me for no reason at all chocking me pulling my hair over family issues he's having...Should I leave him I dong know what to do....