The defence department said last week HMAS Darwin discovered 449 kilogrammes of heroin with an estimated street value of Aus$132 million in a separate bust off Somalia's coast.
The two operations follow a joint seizure of 1,032 kilograms of heroin with an estimated street value of Aus$289 million by the Australian and British navies - their biggest haul - in late April from a dhow off the coast of east Africa near Kenya and Tanzania.
HMAS Darwin is part of the Combined Maritime Forces (CMF) naval partnership in which 30 nations patrol 2.5 million square miles of international waters.
The warship enforces maritime security with a focus on terrorist activity in the Middle East and Indian Ocean regions as part of the British-led Combined Task Force (CTF) 150, which operates under the CMF.
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