A crew of 11 Montenegrins attempted to smuggle 20 tons of hashish across the Mediterranean before they were intercepted by Italy's maritime police, Italian authorities said on Thursday.

Officials estimate the drug's value at somewhere between €150 million and €200 million ($173 million and $231 million).

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"The Mediterranean Sea again is confirmed to be one of the world's largest arteries for illegal trafficking," police said. "The results of the operation are the fruit of attentive intelligence gathering and analysis of the ship's routes."

Suspicious Montenegrins

The research and survey vessel Remus was sailing from the Canary Islands towards Turkey, but police noticed the ship had turned off its position transmitter close to the North African coast. Italian authorities obtained permission from officials in Panama before moving in to detain the Panama-flagged vessel in international waters.

According to the police, crew members aboard the ship were behaving suspiciously, prompting the authorities to escort Remus to port in Palermo. Once there, police drained the vessel's fuel tanks to find 650 sacks containing compressed cannabis resin. All 11 members of the crew were arrested for international drug trafficking.

Morocco in northern Africa is the world's biggest producer of hashish. Police believe the drugs were likely destined for the European market.

dj/amp (dpa, AFP)