You could say it is limited to certain areas. In Auckland, the South Auckland area will always come up trumps when talking about crime/gangs etc etc. There are other areas in NZ that get a mention more often than not - Highbury in Palmerston North, Wairoa in the Hawke's Bay, Otara, Mangere, Manurewa and Otahuhu in the South Auckland area, Mangakino in the South Waikato, and other places that don't come to mind at the moment. All these places have alot in common - poverty, crime, gangs, overcrowding?? etc.
Skinheads are the prevelant feature in ChCh (or so I heard)