Six men have been charged after police seized almost 3 tonnes of narcotics worth more than $1.5 billion in Australia's second largest drug bust.

Approximately 2.8 tonnes of illicit drugs were seized, including 1,917 kilograms of MDMA and 849 kilograms of methamphetamine, with a street value of more than $1.5 billion.

Police will allege the consignment originated in Europe before arriving in Australia earlier this month.

Customs chief executive Roman Quaedvlieg said officers acting on an ongoing intelligence operation found the drugs while searching a sea cargo container from Hamburg in Germany last Friday.

Australian Federal Police (AFP) Commissioner Andrew Colvin said the narcotics were concealed with furniture.

Commissioner Colvin said it was the largest Australian seizure of methamphetamine and the second largest of MDMA.

"By any measure this is an enormous seizure of illicit narcotics that have been removed from distribution on our streets," he said.

Approximtely 1,917 kilograms of MDMA and 849 kilograms of methamphetamine were seized by police, with a street value in excess of $1.5 billion. ( AFP )

Commissioner Colvin said the MDMA was in various forms, but mostly powder.

"We have to presume at some point it would be pressed into pills. I understand there are also some pills in that," he said.

Search warrants were executed across New South Wales and Commissioner Colvin said the AFP was hopeful of further arrests.

Three of the men charged appeared in court via video link and have been remanded in custody to appear again next week. The other three will face court on Sunday.

The Commissioner said it was a sophisticated, controlled operation involving AFP, NSW Police and Australian Customs officers.

He added that police managed the delivery of the narcotics to try to identify as many of the people involved as possible.

Police are also working closely with the German federal police and Interpol.

Multiple organised crime groups probably involved in importation

Commissioner Colvin said the investigation would probably determine a number of organised crime groups involved in the delivery.

"Those we've arrested today will allege they're part of the importation. Where they sit in the scale of importation is yet to be determined," he said.

"This obviously has linkages overseas that will take us, I'm sure, into Europe and parts of Asia.

Sorry, this video has expired Authorities did not 'happen upon' drugs, uncovered haul in investigation (Photo: Australian Federal Police)

"There will be a number of people involved, probably a number of organised crime groups."

NSW Police Commissioner Andrew Scipione said the seizure would have a significant impact on organised crime.

"When we talk about 2 tonnes of MDMA, we're talking upwards of 10 million individual doses, tablets," he said.

"The notion of stopping the importation is one thing, but the message that needs to go to those that are in the business of importing these drugs is just as important.

"My advice is go somewhere else, go to another country. Don't bring your evil poison here to Australia."

Mr Quaedvlieg said the bust would bring this year's total detection of illicit drugs at the Australian border to far higher levels than last year.

By the numbers: 2.8 tonnes of narcotics were seized, including 1,917 kilograms of MDMA and 849 kilograms of methamphetamine

2.8 tonnes of narcotics were seized, including 1,917 kilograms of MDMA and 849 kilograms of methamphetamine Total street value of the consignment was $1.5 billion

Total street value of the consignment was $1.5 billion Each kilogram of methamphetamine alone represents 10,000 street deals of methamphetamine

Each kilogram of methamphetamine alone represents 10,000 street deals of methamphetamine Second largest drug bust in Australia's history

Second largest drug bust in Australia's history Largest Australian seizure of methamphetamine and the second largest of MDMA

Largest Australian seizure of methamphetamine and the second largest of MDMA Previous record for methamphetamine seizure was 580 kilograms

"As a comparative statistic, last year across the major drug type - heroin, cocaine, methamphetamine, ecstasy, precursors - Customs and Border Protection seized about 5 tonnes at the border," he said.

"This year has been tracking around the same rate of detections until last week when in a single seizure we've seized 3 tonnes.

"So you can imagine in a comparative sense where we are going to end up this year in terms of seizures."

Prime Minister Tony Abbott, Immigration Minister Scott Morrison and Justice Minister Michael Keenan commended the efforts of the agencies involved in the drug bust.

"The joint operation between Commonwealth and NSW law enforcement and border agencies has put a major dent in the operations of organised crime in Australia," they said in a statement.

"These agencies have worked tirelessly to ensure these drugs did not reach our streets.

"Potentially thousands of lives have been saved today as a result of the excellent work of our police and law enforcement agencies."