In extraordinary series of revelations on Tuesday, the Australian Federal Police publicly revealed the Calabrian-based network known as the 'Ndrangheta has been using a combination of legitimate businesses in construction, agriculture and catering as fronts for its criminal operations. They said it was using outlaw motorcycle gangs as distributors and go-betweens, and was "pulling the strings" of the bikies.

The revelations comes from investigations resulting from police eavesdropping on an encrypted phone network widely used by organised crime networks last year, known as Operation Ironside.

Assistant Commissioner Nigel Ryan said that 51 Italian organised crime families had been identified in Australia, and 14 were confirmed 'Ndrangheta-affiliated clans, involving thousands of members.

"The 'Ndrangheta are flooding Australia with illicit drugs and are pulling the strings of Australian outlaw motorcycle gangs, who are behind some of the most significant violence in our communities," he said.

"They have become so powerful in Australia that they almost own some outlaw motorcycle gangs, who will move drugs around for their 'Ndrangheta financiers, or carry out acts of violence on behalf of the 'Ndrangheta."

Crime bosses based in Calabria are understood to be controlling the operations in Australia in which billions of dollars generated by drug sales, particularly cocaine, is at stake.

"Australians are, per capita, some of the highest drug users in the world," Assistant Commissioner Ryan said, with consumers willing to "pay top dollar" for the product.

"It [the illegal drug trade] is all based on greed, all based on making money."

Assistant Commissioner Ryan said these clans had operated legitimised businesses in Australia for decades living "under the radar by living modest lives, in modest homes".

"They mix their illegitimate money with money from their legitimate construction, agricultural or catering businesses and all of this makes it more difficult to not only identify criminality but to prove it,'' he said.

These latest revelations about the long-running influence of organised Italian crime again refuel the debate around the involvement of the 'Ndrangheta in the murder of Australian Federal Police assistant commissioner Colin Winchester in a Deakin driveway in January, 1989.

David Harold Eastman was arrested and charged with the murder and served 19 years in jail. Eastman was acquitted in 2014, paid over $7 million in compensation, and has since disappeared from public view.

However, during the inquest, trial and subsequent enquiry into the murder, it was revealed that the slain senior federal police officer had been a key figure in police Operation Seville, which aimed to identify key figures of the 'Ndrangheta crime syndicate, also known as L'Onorata, or the "Honoured Society".

During Operation Seville, 11 Italian men - the so-called "Bungendore 11" - linked to the 'Ndrangheta had been under police surveillance in the early 1980s and were due to face court. All charges against the men were later dropped when a key police informant failed to testify.

A number of the Canberra and Griffith-based men named in the court proceedings still have their identities protected, and their names cannot be published.

During the early 1980s, two large crops of cannabis were under cultivation in the Tallaganda State Forest known as Bungendore 1 and Bungendore 2. Italian organised crime was involved in both these large-scale cultivations and the operation sanctioned in order for police to link the drug sale and the money generated by the crops to high-ranking Calabrian organised crime members via Operation Seville.

However, at least part of the drug crops were harvested without police knowledge and millions of dollars went missing.

Evidence given to the 1990 Winchester inquest revealed documents seized by police from the home of one of the Bungendore 11 described a blood-letting initiation rite by the 'Ndrangheta involving members of the secret Calabrian society cutting their thumbs in the shape of a cross.

Written in Italian, the so-called "rules of sgarro" involve details of "tirata", in which blood is let from the thumb as a sign of loyalty to the clan, and kissing the chief of the society on the forehead after being elected.

Assistant Commissioner Ryan believes the Calabrian crime syndicates have existed in Australia "for generations" and have been able to maintain a low profile through familial discipline and using elaborate finance and communications networks, some of which was exposed last year during Operation Ironside.

"The illegal criminal activity is legitimised by running legitimate businesses," he said.

"People could be living next door to [members of the] 'Ndrangheta and not even know it."