Police said a small plane that crashed shortly after takeoff in Papua New Guinea was overloaded with cocaine destined for the Australian market.
Officers say the “greed” of the drug gang played a role in their downfall.
The Cessna is believed to be carrying over 500 kg (1,100 lbs) of cocaine worth A $ 80 million ($ 57 million; £ 44 million) when it crashed on Monday.
Five men, all allegedly members of a Melbourne-based crime syndicate, have been arrested.
In a statement, Australian police said the gang had been under surveillance for two years. The light plane had taken off from Mareeba in northern Queensland on Sunday and was flying low to avoid radar detection before landing at an airfield remote from Papa Lea Lea, north of Port Moresby.
Police say he was then charged with drugs for the flight back to Australia.
“AFP (Australian Federal Police) alleges that greed played an important role in the activities of the union and cannot rule out that the weight of the cocaine had an impact on the ability of the plane to take off,” said the police in a statement.
The aircraft wreckage was found abandoned and empty a short distance from the airfield. The drugs, in 28 bags, along with an unspecified amount of Australian currency were later recovered by Australian and Papua New Guinea police.
The pilot – an Australian – visited the Australian consulate in Papua New Guinea on Tuesday, police added. He was arrested and charged with an immigration offense.
Police said the five men had ties to Italian organized crime and were arrested in Queensland and Victoria shortly after the plane took off for Papua New Guinea. If they are found guilty, they risk life imprisonment.
“These arrests prove that whatever the sophisticated or opportunistic attempts of organized crime, or the methods they use, the police keep pace and cause the maximum damage to these criminal enterprises,” said the commissioner. AFP deputy Ian McCartney.