Two gang members have been arrested for wearing patches in public.
At midnight, the Gangs Act 2024 came into force which prohibits the display of gang insignia in public.
It also allows police to order gang members in public to disperse, and to apply for a court order banning "association and communication" between specified offenders for three years.
Police Minister Mark Mitchell said just before 11am, police in Wairoa arrested a gang member for wearing a patch to the supermarket.
Around the same time in Auckland's Papakura, a patched Mongrel Mob member was seen by police standing in the street, leading to his own arrest.
Both gang members will face enforcement action, Mitchell said.
It comes after a Napier man was issued with a summons to appear in court after officers spotted a large Mongrel Mob sign on the dashboard of his car in Hastings - just three minutes after the ban started.
While compliance with the legislation was high, Mitchell said it was still early days.
"There is a very simple message to gang members worried about police having the ability to lock them up or search their home; comply with the legislation."
The new offence carries a fine of up to $5000 or six months' imprisonment.
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