In the past 12 months, the Brisbane man played "a significant role" in importing almost two tonnes of cocaine to Australia using sea routes, police said.

The combined estimated street value of these drugs was $683 million.

The Australian Federal Police said the Brisbane man has been involved in 20 conspiracies to import a further 20 tonnes of cocaine, methamphetamine and heroin into Australia since November 2023.

However, the 36-year-old's alleged offending did not end with drug trafficking.

He was also accused of using violence and threats to collect debts and intimidate rivals by asking alleged criminal associates to assault, firebomb, shoot at and extort his customers.

Police said he used encrypted message services to run "illicit adventures" under the pseudonyms 'John Dillinger' and 'WANTED'.

The Brisbane man is accused of facilitating a drug delivery that caused hundreds of kilograms of cocaine bricks to wash up on "beaches where our children play, swim and eat", police said.

The mysterious bricks labelled 'Zoe' and 'Tesla' were allegedly destined for Brisbane and dropped into the ocean from a cargo ship in November 2023.

Police said the drug collection was unsuccessful due to adverse weather conditions.

The first suspicious package was found washed up on the Central Coast at Magenta Beach in December 2023.

In the following week 124 one-kilogram bricks of cocaine were retrieved from beaches between Sydney and Newcastle.

Only 256 kilograms of the suspected 900 kilograms of cocaine has been seized, police said.

"In August last year, we will allege this individual coordinated the importation of 565 kilograms of cocaine into Western Australia," police said.

"Six people have already been charged by the AFP in Western Australia.

"We will also allege that in March of this year, the man conspired to import 450 kilograms of drugs into Queensland via a bulk carrier."

He was arrested leaving a gym in Brisbane's northern suburbs on April 17.

Anyone with information that may assist is urged to call Crime Stoppers on 1800 333 000.

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