Displaying gang patches in public places will not be tolerated, police say, once new laws come into effect on 21 November.
Police had been meeting with gangs to discuss the changes, assistant commissioner Paul Basham said.
"Gangs are well aware that once this law comes into effect, they are not allowed to wear a gang patch in public.
"Police staff have spoken to gang leaders and made it clear that anyone breaching the new laws can expect enforcement action."
If police came across anyone wearing gang insignia in public, the excuse of ignorance would not be taken as a defence, Basham said.
Police dubbed the nation-wide operation to enforce new laws Operation Nickel and Basham said the police's gang disruption unit had been set up and was ready to go.
"These teams are situated nation-wide and are focused on disrupting criminal gang activity.
"They will be gathering evidence of criminal behaviour including breaches of the Gangs Act," Basham said.
Calls for service would still be prioritised, Basham said, which could mean a breach would occur and police would not be able to attend at the time.
"In these cases, wherever possible we will be gathering available evidence to follow through with enforcement action at a later time."
The gang disruption units would follow up on reports of breaches and do search warrants to recover patches and insignia.
Laws passed under the Gangs Legislation Amendment Bill would also allow police to issue dispersal notices and non-consorting orders to stop gang members from associating or communicating for up to three years.
"Our message is simple - Parliament has passed a law, it's our job to enforce the law, and we will be enforcing it.
"If you don't want to have enforcement attention from police, don't breach the law," Basham said.
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