Claims short and long term approaches are needed to crack down on New Zealand gangs

Over the weekend, South Auckland's Otara saw three shootings - and Counties Manukau Police will now carry firearms until further notice.

Canterbury University criminal justice director, Jarrod Gilbert, says strong policing is important when gangs are firing guns in the streets.

But he says the biggest challenge is stopping people joining gangs.

He says people join gangs for a number of complex social and economic reasons, and if we don't counter these, gang activity will continue.