Six people including four British men have been arrested in Australia and New Zealand in one of the region's largest-ever drug seizures.
Australian police said the bust was connected to a UK-based organised crime syndicate which supplied highly pure methamphetamine and MDMA powder.
Drugs with an estimated value of A$90m (£50m; $61m) were seized in the state of Queensland.
The drugs could have made up to 12 million ecstasy capsules, police added.
Queensland Police said it was the third-largest MDMA bust in Australia's history and the drugs were the "highest purity" ever seized in the state.
Police arrested two British men, aged 40 and 51, an Australian man, 26, and an Australian woman, 51.
Another two British men, aged 49 and 60, were arrested in Auckland, New Zealand last week after police there seized 200kg of methamphetamine.
Raids were also carried out in the Australian state of New South Wales.
"Organised crime syndicates are making significant profit at the expense of our Australian community," Queensland Police said in a statement.
"Police believe the powder was destined for production into pill and capsule form to be sold across Australia."
MDMA is the active drug found in ecstasy tablets.