Trusted insiders are using their knowledge of the nation's border controls to get drugs into the country and the problem is getting worse, the Australian Border Force commissioner says.
ABF officers detected some 11 tonnes of illicit drugs at the border last financial year, up from eight tonnes in 2019-20.
But detections at the border only represent between 20 and 30 per cent of total important quantities, ABF Commissioner Michael Outram said during a speech at the Ports Australia conference in Brisbane on Wednesday.
The level of criminality in the supply chain is now at a critical level according to information from the force's partners, he said.
"Just before Christmas, the ABF intercepted a shipping container in Brisbane with 50 kilograms of cocaine concealed within the refrigeration unit," he said.
"The cocaine was placed there by criminals who had infiltrated the supply chain offshore, and of course it was to be removed by people working within the supply chain here in Australia."
Last month, ABF officers investigated a number of sea cargo containers that arrived at Port Botany in Sydney.
They found 748 kilograms of methamphetamine concealed in marble stone.
Further examination of more containers at Port Botany found a further 1060kg of methamphetamine also hidden in marble.
The estimated potential street value of the ice seized was more than $1.6 billion.
In June 2021, the Australian Federal Police confirmed criminal infiltration within air and sea supply chains had reached a scale of national and international concern.
Those on the inside can include workers at depots and warehouses, customs brokers, shipping companies and airlines, as well as stevedores and "of course the Australian Border Force and our partner agencies," Mr Outram said.
"They know where to conceal things, how to get around us."
Law enforcement has a role to fix the insider issue, but Mr Outram admits "you can't arrest our way out of this kind of problem".
"We've had a crack at this problem over the years, mainly through joint task forces. Yet, the problem hasn't only persisted, it's gotten worse," he said.
He believes a more systemic approach is also needed.
"We identify the vulnerabilities and the weaknesses within businesses, the methodologies and people of concern," Mr Outram said.
Administrative legal powers are then used to put them out of business, or a case is made for policy, regulatory or technological change to disrupt criminal business models.
Using intelligence to identify consignments of concern is vital, however there also needs to be a significant investment in automating non-intrusive screening methods at an industrial level.
Without this step, Australia "will fail to secure our border properly and our national resilience will be severely undermined as a consequence", Mr Outram said.
There is also potential for greater integration between screening processes for illicit drugs and those designed to pick up agricultural pests and disease.
At Australia Post's international mail screening, there are separate conveyor belts for ABF and agriculture detection processes, Mr Outram said.
"We are very much on that journey...with the department of agriculture in particular, in bringing those processes together," he said.