Armed Serbian police stormed a Belgrade hotel to arrest three Australian citizens suspected of being part of an international drug-smuggling group.
Police alleged the men "are linked to" the discovery of 1,280 kilograms of cocaine that was seized last April on a Chinese boat docked in Sydney.
They said the drugs were worth $500 million.
Police released footage of the arrests that took place in the lobby of the hotel, with the men putting their hands in the air before being handcuffed.
Authorities in Belgrade said two of the Australians were in their late 40s with another in his mid-30s.
A bag filled with foreign currency banknotes from Europe, Australia, China, Thailand, Singapore and Vietnam also was shown, and police said the arrests were made during a "money handover".
A gun was also found.
A Lebanese citizen was detained and charged with having forged identity documents.
Serbian authorities said the arrests were made in cooperation with Australian police.