The teen flashed a gun as he fought with another youngster inside Hollis Playground at 204th Street and Hollis Avenue in Queens Village around 3:40 p.m., cops said.
In the most recent attack, a 38-year-old man was walking in the mezzanine of the Canal Street N, Q and R station around 4:25 a.m. Wednesday when six muggers -- who appeared to be no older than teens -- approached him and grabbed his wallet, holding $15, police said.