Huge cocaine bust sparked by drugs floating in water

Two men have been charged as part of an ongoing probe into Australia's largest cocaine seizure.

Brisbane man Richard Huynh, 41, has been arrested after being accused of facilitating the shipment of almost three tonnes of cocaine from Queensland to NSW and Victoria through a transport business.

A 23-year-old Sydney man has been also been accused of being part of a criminal syndicate after allegedly being found with a semi-automatic 9mm pistol and a loaded sawn-off shotgun along with ammunition and a silencer.

He faces a string of firearms and drug charges as Operation Minjiang continues.

A total of 12 people now remain before Queensland and NSW courts in relation to the ongoing operation launched three months ago.

It was triggered by the discovery of 40kg of cocaine floating in the water, close to a burnt-out truck at Midge Point near Mackay on the central Queensland coast on May 30.

It led to Australian Federal Police uncovering a stash of 2.7 tonnes of cocaine under shipping containers in western Sydney on June 19.

Officers discovered the drugs, with an estimated value of $816 million, buried under the false flooring.

It was the biggest Australian drug bust in nearly 20 years, and second only to the seizure of 4.5 tonnes of MDMA in Melbourne in 2007.

Huynh was charged after a Kangaroo Point home was searched and $80,000 in cash and electronic devices was seized.

Several electronic devices were also seized for digital forensic analysis, police said.

Australian Federal Police allege other syndicate members moved 2.78 tonnes of cocaine from a suspected safehouse in Brisbane's north to a Loganholme location in the city's south.

Huynh is accused of facilitating the interstate shipment of the cocaine from Loganholme through the trucking logistics business before the drugs were moved to Sydney's west.

"The logistics business is not believed to have any involvement or knowledge of the offending," Australian Federal Police said on Friday.