Police in Sydney, seized 2.8 tonnes of illicit drugs worth an estimated A$1.5 billion (US$1.27 billion) on Saturday, media reported.
The massive cache of illicit drugs constituted the second biggest confiscation of drugs in Australia's history, the Sydney Morning Herald reported.
The confiscated drugs included 1,917 kg of MDMA (Ecstasy) and 849 kg of methamphetamine (speed and ice). It was the single largest seizure of ice in the nation's history and the second largest seizure of Ecstasy.
The narcotics were shipped to Australia from Hamburg, Germany, in a single consignment and arrived on November 19, police said.
Delivery of the container was tracked, first to Blacktown and then to Smithfield, both in western Sydney.
Six men aged between 23 to 34 years were arrested and charged with serious drug importation offences, following the major police operation.
"By any measure, this is an enormous seizure of illicit narcotics," Australian Federal Police Commissioner Andrew Colvin said.
"It's also a bold attempt by organised crime to target this country with large illicit narcotic importations," he added.
New South Wales Police Commissioner Andrew Scipione said the seizure revealed "organised crime at its worst" and "law enforcement at its best".
The investigation was in its early stages and police were confident of making more arrests.
"The amount of drugs that we consume as a nation is something that is disturbing," Scipione said.
New South Wales premier Mike Baird noted the drugs were being imported in the lead-up to the summer party season and said the seizure had potentially saved many lives.
"This was a bust (confiscation) of epic proportions and thankfully, none of these drugs will see the light of day," he said.
The 2.8 tonnes of narcotics represented more than half of the total amount seized by Australian customs officials in 2013.