Over 118,000 cigarettes worth more than €70,000 were seized by Revenue officers off the coast of Dublin.
Authorities aboard Revenue Customs Cutter Faire made the discovery during a search of an Italian registered merchant vessel.
The ship was detained when officers found 118,140 cigarettes branded “L&M”, “Malboro”, and “Winston” with an estimated retail value of over €70,000 representing a loss of around €56,000 to the Exchequer.
The vessel was released on the penalty payment of €50,000.
A Revenue spokesman said: “Investigations are ongoing.
“This seizure was part of Revenue’s ongoing operations targeting the shadow economy and the supply and sale of illegal tobacco products.
“If businesses or members of the public have any information regarding the smuggling they can contact Revenue in confidence on free phone number 1800 295 295.”
