Two men and a woman have been charged after authorities uncovered a bounty of steroids and peptides worth more than $2 million.
The bust, announced on Friday by the Australian Border Force and Therapeutic Goods Administration, was set in motion in August following the interception 640 vials of performance and image enhancing drugs from air cargo shipments.
A subsequent probe revealed another 76 similar shipments had been made to the same recipient since April 2025.
Officers from the two federal agencies found more than 10,000 vials and 600 tablets in March 26 raids on a commercial site and residential home in Melbourne's west.
Cannabis seeds and several digital devices were also confiscated.
A 47-year-old Victorian man was arrested and charged with two counts of importing performance and image enhancing drugs.
A further raid on March 31 led to the discovery of more steroids and peptides, cannabis, six pepper sprays and a taser, with a 46-year-old man and 42-year-old woman later arrested and charged with the same offence.
The trio have since been granted bail and are scheduled to next face court in August.
The joint investigation reinforced the importance of strong collaboration to protect public health, Therapeutic Goods Administration head Anthony Lawler said.
"Unapproved steroids and peptide products present serious and unacceptable risks to consumers, particularly when they are injected and manufactured outside of regulated supply chains," Professor Lawler said.
"Working closely with enforcement agencies such as the Australian Border Force and Victoria Police allows us to disrupt unlawful activity early, prevent dangerous products from reaching the community, and hold those responsible to account."
News of the arrests comes just days after the national medicine regulator issued a safety advisory over the rising importation, supply and advertisement of unapproved peptide products.
Peptides are chains of amino acids, while steroids are synthetic hormones.
Unapproved peptide products are increasingly being promoted online with claims of wide-ranging health benefits.
They are often supplied in injectable form and can carry significant safety risks, including contamination, infection and tissue damage.