More than 200 members of Australia's mafia and bikie underworld have been charged in the nation's largest-ever crime sting, police say.

Key points:

• Police say more than 200 arrests have been made in connection with Operation Ironside
• AFP officers tracked criminal underworld figures using an encrypted messaging app
• The first arrest from the operation occurred on November 8, 2019

As part of a three-year collaboration between the Australian Federal Police (AFP) and the Federal Bureau of Investigation (FBI), underworld figures were tricked into communicating via an encrypted app designed by police, authorities say.

The app, known as AN0M, was used by organised crime gangs around the world to plan executions, mass drug importations and money laundering.

Authorities say they were able to read up to 25 million messages in real time.

Police said they uncovered 21 murder plots and seized more than 3,000 kilograms of drugs and $45 million in cash and assets.

Operation Ironside sting was a 'massive blow' to organised crime according to authorities Hakan Ayik unwittingly distributed the app to his associates.(

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The AFP said the operation prevented a suburban mass shooting in Australia, with the plan involving the use of a machine gun at a cafe.

Authorities said a family of five was the target of another plan uncovered by the sting.

Last night, more than 300 search warrants were carried out across Australia, with simultaneous stings in the US and Europe.

Prime Minister Scott Morrison today said the operation had "struck a heavy blow against organised crime. Not just in this country, but one that will echo around organised crime around the world".

"This is a watershed moment in Australian law enforcement history," Mr Morrison said. 

"Our investments … have enabled [the AFP] to be part of major partnerships and take a leading role to spearhead this assault on organised crime." 

Minister for Home Affairs Karen Andrews said the statistics from the operation were "astounding".

Triads, drug cartels exposed

The sting, known as Operation Ironside, has allegedly exposed criminals linked to South American drug cartels, Asian Triads and Middle Eastern and European criminal syndicates.

Police said dozens of members of the Comanchero and Lone Wolf outlaw motorcycle gangs had been arrested.

More than 100 firearms were seized during the raids.(

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There have been arrests across 18 countries, including the United States, UK, Germany and New Zealand, with more expected. 

Police said the plan to use an encrypted app was hatched overseas over a few beers with FBI agents in 2018, before police figured out how to decrypt all messages.

The AFP built a capability to access decrypted communications between customised mobile phones.

These handsets were modified so they could not call or email and people could only communicate with someone else on the same platform.

Operation Ironside stats

• 4,500 Australian officers involved
• 500 search warrants executed
• 224 people charged with more than 525 offences
• 104 firearms seized
• $45 million in assets and cash seized
• 3.7 tonnes of drugs taken from syndicates
• 33 countries involved 

The app was unwittingly distributed by fugitive Australian drug trafficker Hakan Ayik, after he was given a handset by undercover agents.

Ayik, 42, recommended the app to criminal associates who would purchase the handset pre-loaded with AN0M on the black market, allowing them to send messages, distort messages and take videos.

Police said in some cases it took months to establish whom a specific handset was being used by.

AFP Commissioner Reece Kershaw said Ayik was a marked man and should turn himself into Australian authorities.

"Given the threat he faces, he's best off handing himself into us as soon as he can," he said.

"He was one of the coordinators of this particular device, so he’s essentially set up his own colleagues."

NZ police arrest 35 people and seize $3.7 million in assets as part of 'Operation Ironside'

Authorities said about 4,000 police raided properties this week, with the investigation growing so large the AFP had paused its operations over the past few weeks, except for those relating to child protection and counter-terrorism.

More than 11,000 people were using AN0M devices across the world, including 1,650 in Australia.

Half of the criminal activity detected on the app was in New South Wales.

More than 300 search warrants were carried out across Australia.(

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Police conducted 210 search warrants yesterday, which they said broke the previous record of 50 search warrants in a single day. 

Commissioner Kershaw said federal agents had been in the "back pockets" of criminals through the encryption app. 

"The FBI had the lead on this. We provided the technical capability to decrypt those messages," Commissioner Kershaw.

Authorities said about 4,000 police raided properties this week.(

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) Reece Kershaw addressed the media as Scott Morrison looks on.(

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"Some of the best ideas come over a couple of beers." 

The Commissioner said criminals on the app were "very brazen", making no attempt to hide their activities through coded messages.

"All they talk about is drugs, violence, hits on each other, innocent people who are going to be murdered," Commissioner Kershaw said. 

"It was there to be seen." 

He said legal authorities prevented the app from being covertly used for a longer time frame.

'Just the beginning'

Since Sunday, NSW Police has had more than 1,000 officers in the field carrying out 33 search warrants and assisting AFP with dozens of others.

Thirty-five people have been arrested locally, mostly over alleged drug distribution.

Investigations and Counter Terrorism Deputy Commissioner David Hudson said while today was a good day, it was "just the beginning".

David Hudson said the police sting was "just the beginning".(

ABC News: Tim Swanston

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"Today has been significant in shutting down a number of criminal enterprises across NSW," he said.

"This is an ongoing process when we take out certain components of the criminal element.

"Someone will always be there to try and replace it and that is what we are most concerned of in the future and ongoing."

He said the recent bolstering of Strike Force Raptor and the serious crime squad was partly done in preparation for "what will happen next".

"We have seen that when we have an impact … there will be reprisals, there will be debts owed, there will be conflict," he said.