Australia’s largest ever shipment of the deadly opioid fentanyl has been intercepted in Melbourne.

More than 11 kilograms of pure powdered fentanyl and 30 kilograms of methamphetamine was found inside an industrial wooden lathe at the Port of Melbourne in December last year.

It took authorities two weeks in February to safely remove and analyse the drugs, which were sent from Canada.

Forensic officers had to wear protective biohazard suits while removing the fentanyl as any skin contact could cause harm or loss of consciousness.

The operation included having Ambulance Victoria on standby during the extraction and deconstruction.

Fentanyl is a fast-acting opioid that is highly addictive and acts similarly to heroin.

A single dose of 28 grams can kill a person.

“We were absolutely shocked by the size of the detection and the audacity of this attempted importation,” Australian Border Force Commander James Watson said on Monday

“I describe it as a total act of bastardry, quite frankly.”

The drug is primarily used for medical purposes in Australia but it’s becoming used more prominently overseas for illicit reasons.

Australian authorities have previously seized only minor amounts of fentanyl, totalling less than 30 grams.

The 11.2 kilograms of pure fentanyl seized in December was the equivalent of about 5.5 million doses.

The methamphetamine had an estimated street value of $27 million. Police said there was no precedent to estimate a street value for such a large amount of fentanyl.

“The impact of this on our community had it reached our streets, it just doesn’t bear thinking about,” Mr Watson said.

The Australian Federal Police are yet to charge anyone in relation to the December intercept.

“There is someone out there in the community who does know more,” AFP acting Commander Anthony Hall said.

“We’re appealing to that person or persons to speak up and call Crime Stoppers.”

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– with AAP