Three men have been charged and hundreds of kilograms of methamphetamine seized as part of a probe into a Mexican organised crime syndicate operating internationally.
It's alleged the syndicate sent 375kg of methamphetamine from Los Angeles to Sydney in five shipments from April 2022 to February 2023.
Authorities say the cartel was also responsible for drug shipments seized in Hong Kong and New Zealand.
The operation allegedly involved cocaine and methamphetamine hidden inside electrical transformers and plastic pellets.
The breakthrough came in February 2023 when 85kg of methamphetamine hidden inside 13 plastic pellets was detected in Los Angeles.
The haul had a street value of about $76 million and was secretly substituted with a harmless substance when it arrived in Sydney.
Australian Federal Police investigators allege two US nationals, aged 42 and 34, flew to Sydney to facilitate the shipment and a 40-year-old Sydney man is the local contact for the syndicate.
The trio allegedly transferred the pellets from a storage facility in south western Sydney to the north shore in April.
All three were arrested and charged with one count of attempting to possess a commercial quantity of a border controlled drug, which carries a maximum penalty of 25 years behind bars.
Australian Federal Police Detective Superintendent Kristie Cressy said intelligence sharing between countries was a crucial part of the operation.
"The arrest of three people here in Australia and their connection to a wider Mexican-based cartel gives us valuable insight into the operations of organised crime groups and will help us and our partners create a hostile environment for them to operate in," Det Supt Cressy said.
The men faced court on May 2 and will next appear on July 27.
It's alleged more than 650kg of liquid methamphetamine and cocaine seized in Hong Kong and New Zealand since 2019 were also bound for Australia.