Australian police say they have made their largest-ever seizure of the drug methamphetamine hidden in a shipment from southern China.
The drugs weighed a total of 585kg (1,290 pounds) and had an estimated street value of A$430m ($440m: £291m).
Three men – a Singaporean, an Australian and a Hong Kong man – have been arrested and are due to appear in court in Sydney on Thursday.
Police said further arrests in Australia and abroad were possible.
The suspects face a maximum life sentence if found guilty.
At a news conference, Australian police said the drug, known as “ice”, was seized following a four-month investigation triggered by a tip-off by a member of the public about suspicious activity at storage facility in West Ryde, Sydney.
It had been brought over from Shenzhen, China, inside a shipment of cleaning chemicals.
“This is a hideous, insidious drug. This is the sort of drug that sends people mad,” said New South Wales Police Commissioner Andrew Scipione.
“That one phone call was the one thread that allowed us to pull and unravel a syndicate that will be stopped forever.”
The investigation involved the Australian Federal Police (AFP), Customs officials, New South Wales Police and the Australian Crime Commission.
AFP Commissioner Tony Negus said the drugs syndicate had gone to “considerable lengths to escape detection”, but that the police operation was not yet over.
“We’ve not ruled out further arrests either here in Australia or overseas,” he said.
“We’ve already been in contact with authorities in China and a range of further inquiries are under way.”
The haul is nearly double the size of the last record haul of 300kg, made last year.