Key Points:

Street gangs have been committing vicious pack rapes during drunken rampages across Auckland City, a senior policeman has revealed.

The western part of the city has a thriving street gang scene, with 400 members and up to three times as many associates.

And with that comes serious street gang crime. Police area commander Inspector Jim Wilson lists the murder of 14-year-old Manaola Kaumeafaiva at the gates of Avondale College in October and four rapes as the among the worst.

He said the pack rapes were opportunistic and fuelled by alcohol. Victims were selected at random and one rape had taken place in a garden shed.

Mr Wilson had other examples: the gang who held a victim down and swung a golf club into his face, causing $22,000 worth of dental damage, and a series of fights that could have ended in death "if not for the wonders of modern medical science".

Mr Wilson said the western area of Auckland City was plagued by the same street gang problem as South Auckland. A "crime corridor" running from Otahuhu to New Lynn comprised many gang hotspots, particularly in the poorer areas. Mt Roskill was a particular stronghold.

A Weekend Herald investigation revealed that 10 killings in Auckland in the past two years had been linked to youth or street gang violence.

Mr Wilson said it was along this corridor that police intercepted a South Auckland gang travelling to fight one of the west city gangs.

The convoy was spotted by the Eagle helicopter and police stopped it in Wesley, "getting literally in the middle" to stop the battle, seizing machetes, bats and poles.

The numbers of street gang members had "quadrupled" in the past two years, Mr Wilson said, but police were successfully cracking down on them.

"We won't accept criminal street gangs and the community doesn't have to either," he told the Herald. "Give us a ring on 111 and we will be there. Don't be afraid of retaliation."

Mr Wilson said the street gangs were also involved in drug distribution, and police had stamped out an operation that was dealing cannabis laced with P designed to ease the young into methamphetamine.

The gangs were also involved in organised crime.

One gang was arrested for stopping passengers as they got off a bus and frog-marching them to an A" machine and forcing them to withdraw money. Another was caught pimping underage prostitutes.

Mr Wilson said the gangs were involved in "volume crime", such as large numbers of burglaries, done to buy drugs or at the behest of older gang members.

The two main street gangs in the area are the DMS - Dope Money Sex - and the JDK - Junior Don Kings. Each has about 60-70 members, feeder gangs and many more associates.

Like the South Auckland gangs, they had a heavy presence on the Bebo social networking website, and are producing their own rap songs.

Mr Wilson said as many members were in their twenties, using the term "youth" gangs was a "misnomer".

"They are organised criminal street gangs and should be referred to as such," he said.

Mr Wilson has initiated a Youth Action Team to target street gangs. It comprises uniformed officers, a detective and a graffiti analyst.

A group of volunteer Pacific wardens has also been set up and assists police at street gang hotspots.

STREET GANGS

* Believed to be 2000 members Auckland-wide.
* 1500 already individually profiled by police.
* 1000 in last South Auckland estimate.
* 700 in Auckland City.
* 300 in North Shore and Waitakere.