Australian police have seized 720 litres of methamphetamine with an estimated street value of A$1bn (£490m), hidden in gel bra inserts and art supplies.
Four people have been charged over their alleged involvement in importing and manufacturing the drug.
The joint organised crime group operation involved the Australian federal police, New South Wales police, Australian Border Force and Australian Crime Commission.
“This has resulted in 3.6m individual hits of ice being taken off our streets with a street value of $1.26bn,” NSW justice minister Michael Keenan told reporters in Sydney on Monday.
Officials said the operation began in December when Border Force examined a shipping container out of Hong Kong.
“That shipping container was found to contain gel bra inserts and hidden inside those gel bra inserts was 190 litres of liquid methamphetamine,” Commander Chris Sheehan said.
An additional 530 litres were found during the inquiry by joint organised crime investigators.
“These drugs were concealed inside art supplies housed in five storage units in Sydney in the suburbs of Miranda, Hurstville, Padstow and Kingsgrove,” Sheehan said.
A 33-year-old Hong Kong national was charged over the original seizure. Following his arrest, another three Hong Kong nationals – a 59-year-old man, a 37-year-old man and a 52-year-old woman – were arrested and charged over the drugs located in the storage facilities.
“This has been a very good day for Australian law enforcement and a very bad day for the organised criminals that have targeting the Australian drug market,” Keenan said.
Australia has one of the world’s highest rates of methamphetamine usage. The Australian Crime Commission said in March 2015 that as many as 1.3 million Australians had tried ice or speed, with nearly 400,000 using in the last 12 months.
Research in 2014 from the Australian Institute of Health and Welfare showed that while methamphetamine usage had remained stable since 2010, the proportion within that of users taking the crystal form – otherwise known as ice – had markedly increased.
The purity of the drug in its crystalline form, the high demand and the relative success of law enforcement in intercepting imports means the price of the drug is higher in Australia than nearly anywhere else in the world, police said.
Australians pay nearly US$500 a gram compared with an average street price in China of US$80 a gram. Wholesale prices in Australia ranged from $90,000 to $325,000 a kilogram, a report from the Australian Crime Commission found.
The massive profit margin has made Australia an attractive destination for criminal gangs involved in the manufacturing and trafficking of methamphetamines.