Italy's Guardia di Finanza (GDF) finance police swooped on the boat 130 nautical miles southeast of Sicily after tracking the vessel from the air for two days, a statement said, arresting all nine members of the vessel's crew.
The GDF said that the drugs recovered from the boat were of a sufficiently high quality that it had a market value of between 15-20 million euros ($17.7 million-$23.6 million).
Two of the detained, including the first officer, have been identified as members of a "dangerous" Maltese criminal organisation, the authorities said. They had been arrested in Spain last summer in a joint operation between the GDF and Spanish police for trafficking 6,000 cases of contraband cigarettes.
Another suspect was a Sicilian whose criminal record contains previous conviction for armed robbery.
The raid was part of an international anti-drug trafficking initiative called "Libeccio International" -- Libeccio being a southwesterly wind that sweeps Italy and Corsica -- in which Italy collaborates with a number of other European nations.
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