Police have arrested 12 people and issued more than 180 infringement notices at a gang gathering in rural Nelson.
Of the arrests, just one was for wearing gang insignia, which is now illegal under the new gang patch laws.
The changes to the Gangs Act to ban patches or gang insignia in public have been in force for over a week.
The other arrests were for breaching bail and release conditions, drug possession, and driving offences.
Three vehicles were impounded and 182 infringement notices handed out.
Of more than 2800 breath tests conducted, just two returned results over the legal breath alcohol limit, police said.
Locals spoken to by officers were pleased and reassured by the police presence around the event, Tasman district commander Superintendent Tracey Thompson said.
"And our message to gang members is simple - we will not hesitate to enforce the law, including the new Gangs Act, and the way to avoid our further attention is to comply with the law.
"It's pleasing to see that, on the whole, most are doing so, and we want to reassure the public that we will continue to hold people who break the law to account."
A large number of attendees of the gathering had left Nelson on Sunday, but there would be a police presence in the area into Monday, Thompson said.
Gang patch arrests
The arrest in Nelson for allegedly flouting the Gangs Act was one of eight across the country over the past two days.
On Friday, three arrests were made - two in Auckland, and one in Gisborne.
And on Saturday, four arrests were made in Auckland, Te Puke, Taupō and Hastings.
Just one of the arrests was for wearing a gang patch - the rest were for wearing clothing with gang insignia on it.
"Police continue to work to enforce the law, and in general, compliance remains high," Assistant Commissioner Paul Basham said.
The people arrested would appear before the courts in due course, he said.
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