Six men have been charged after almost $1.7 billion worth of methamphetamine was seized as part of a probe into a global smuggling syndicate.

The operation involved four separate hauls in 2023, mostly involving attempts to hid the drug in bottles of canola oil in Canada that were destined for Victoria and NSW.

In January, $720 million worth of liquid methamphetamine was smuggled from Canada to Australia inside 180 bottles of canola oil.

Authorities secretly substituted the drugs for a harmless substance and kept watch as two men allegedly moved it to storage locations in Melbourne before most of it was distributed across Victoria.

In May and June, Canadian authorities seized two further shipments of liquid methamphetamine hidden in canola oil bottles with a combined street value of almost $800 million.

One of the hauls involved 2900 kilograms of the drug, making it the largest methamphetamine seizure on record in Canada.

On Wednesday, federal police executed search warrants at a home and a storage unit in Melbourne, allegedly finding a large quantity of drugs, cash and firearms.

Two men from Melbourne’s CBD, aged 32 and 38, were charged over the January import and were set to face court on Thursday.

The 38-year-old is accused of being a conduit for an organised crime network in Canada while 32-year-old allegedly used his position in a logistics business to transport the substituted drugs once they arrived in Australia.

If found guilty they face a maximum penalty of life behind bars.

A 28-year-old Sunshine North man, a US national, 26, and St Albans man, 19, were charged with attempting to possess a commercial quantity of unlawfully imported border controlled drugs following the searches in Melbourne.

Police allegedly uncovered a clandestine laboratory to manufacture drugs and it’s expected the trio could face further charges.

Meanwhile, a 51-year-old from the CBD was charged with possession and trafficking of a marketable quantity of border controlled drugs, dealing with proceeds of crime and other offences.

It’s expected further arrests will be made.

The investigation involved the Five Eyes partnership, an intelligence alliance involving Australia, the US, Britain, New Zealand and Canada.

In January, six people were charged in New Zealand over a 713-kilogram haul of crystal methamphetamine suspected of being sourced from the same organised crime group bringing the drugs to Australia.

AFP Assistant Commissioner Hilda Sirec said transnational organised crime groups posed a significant threat to national security.

“While organised crime and drug trafficking are not new, what is emerging is the trafficking of illicit drugs in state war craft,” Assistant Commissioner Sirec said.

“In parts of the world, some state actors appear to be working with organised crime to distribute illicit drugs to regions in a bid to undermine societies and democracy.

“This challenges our rules-based order and the rule of law at levels never before seen.”

– AAP