Five of the 11 suspects arrested in connection with a 1.6-ton shipment of cannabis from Albania to Greece were remanded in custody on Friday.
They appeared before a magistrate in Athens a few days after the other six suspects were also sent to Korydallos Prison pending their trial.
The suspected traffickers, all men, are from Albania (six), Greece (two), Italy (two) and Bulgaria (one).
A 31-year-old Italian is alleged to have masterminded the plan to smuggle the drug into Greece on a speedboat. One of the Greeks, a 65-year-old who runs a business renting out speedboats, has admitted to supplying the smugglers with two vessels but insists he did not know about their plans to transport drugs.