A record haul of cocaine worth an estimated 500 million euros (638 million dollars) has been seized from a yacht off the southwest coast of Ireland, police said Thursday.

Three men aged between 44 and 52 have been arrested by Gardai (Irish police) while the investigation continues into what is thought to be the biggest seizure of its kind in Ireland.

`A substantial quantity of suspect packages of what is believed to be cocaine with an estimated street value of approximately 500 million euros (635 dollars), subject to forensic analysis, have been detected on board the yacht,` police said in a statement.

The packages, which were found after naval boarding teams intercepted the yacht in bad weather, will be examined by Irish customs and police officers.

An international anti-drugs mission, Operation Seabight, has been under way for some time. It is led by an Irish joint task force on drug interdiction involving the naval vessel Niamh, police and customs.

The task force got assistance from other organisations such as Britain`s Serious Organised Crime Agency.

Police would not comment on media reports that the 60 foot (20 metre) yacht had been tracked across the Atlantic.

Justice Minister Dermot Ahern congratulated the task force on the seizure and the `great work being done to tackle the supply of drugs into Ireland.`

`Today we have another practical and successful example of different agencies working closely together, sharing intelligence and achieving a fantastic result,` Ahern said.