That's probably because the Sudanese figured highly in Australia's humanitarian refugee intake.
So many may have come here from refugee camps but they came through the front door not by boat.
Presumably these are the kids of those recent arrivals.
I can remember a number of years ago where I live we had similar occurrences between Vietnamese gangs and other ethnic groups.
That's gone quiet now but there is the occasional brawl between Sudanese youth and other groups.
