More than 200 kilograms of cocaine has been seized by Greek police in the harbour city of Piraeus.
Police said on Thursday that the cocaine was hidden in a refrigerated container loaded with shrimp from a South American country. Four men aged between 36 and 64 were taken into custody.
The Greek investigators were put on the trail of the drug gang by a tip-off from the US Drug Enforcement Administration.
Before their arrest, the gang had made around €5 million ($5.4 million) from their trafficking, the police said.
The market value of the cocaine seized is estimated by experts at around €500,000. South-eastern Europe is considered a major hub of the illicit drug trade.