Two Irish-born men are among twelve people arrested following the recovery of five tonnes of cocaine in Spain worth an estimated value of over €332 million.
Spain's most wanted drug baron and a Briton who is an associate of the Ireland-born pair were among those arrested by Spanish police in one of Europe's largest drugs busts.
One of the Irishmen is a resident of Marbella and understood to hold both British and Irish passports while the other is understood to have been born in Ireland but to hold a British passport.
Daniel Baulo Carballo, considered to be the head of a powerful crime gang in Spain's isolated northwest region of Galicia and his brother Carlos were detained in the operation, which came to light late on Monday.
The coves of Galicia are a favourite destination for drug traffickers smuggling cocaine into Europe from South America.
Daniel Carballo took over the leadership of the "Os Caneos" gang after his father was killed in 1994 by Colombian assassins, Spain's Interior Ministry said. The group is considered to be the biggest ring shipping cocaine into Europe by sea, the ministry added.
British and Portuguese police co-operated in the operation that resulted in the arrest of two Irish-born men and three British citizens living in Spain's Costa del Sol. The three are believed to have been trafficking drugs within the European Union, police said.
Police boarded the boat on Friday as the culmination of two years of investigation that began when the British citizens made contact with "Os Caneos" in Portugal.
It was the second major drugs bust in Spain in less than a month. Authorities announced in mid-May they had seized three tonnes of cocaine hidden in furniture imported from Venezuela to the Mediterranean port of Barcelona.