The Celtic League has written to the government of Finland over the Manx-registered ship the Thor Liberty.
The Thor Liberty was stopped while carrying missiles and explosives to South Korea, and the pressure group says it has warned Finnish authorities about past incidents involving Manx vessels and munitions.
Celtic League director of information Bernard Moffatt has contacted the country's interior minister, saying he wanted to warn the Finnish government about Manx-registered vessels which have transshipped weapons cargoes before reaching their destination.
He says in November 2009, a Douglas-registered ship transferred mortar shells, rockets, and hundreds of thousands of rounds of Iranian ammunition onto another ship destined for Hezbollah.
In his letter, he says he has no reason to believe the Thor Liberty's cargo was anything other than legitimate, but it would be prudent to advise Finnish Customs about previous allegations.
The Thor Liberty's skipper and first officer were being held by the Finns on suspicion of transporting defence material via the country without permission.

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