Australian police have seized a record 3 tons of cocaine hidden in underground bunkers on a property near Sydney, marking the largest cocaine haul in the country’s history.

Authorities allege a Sydney-based crime group imported the drugs via a vessel that offloaded the shipment in northern Queensland before it was transported south.

The cocaine had an estimated street value of more than AU$800 million (US$560 million).

Two men were arrested at the property, while six others had already been charged in connection with the trafficking operation, CBS News has reported.

Investigators are continuing to trace the origin of the drugs and identify the international criminal networks involved.