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A luxurious superyacht linked to a Russian billionaire was detained by authorities after docking in Gibraltar on Monday.
Several have headed to the Maldives, which has no extradition treaty with the US.
Reuters TV footage showed the Axioma, believed to belong to Dmitrievich Pumpyansky, owner of Russia's largest steel pipe maker, moored at Gibraltar, a British Overseas Territory on the southern tip of the Iberian Peninsula, flying a Maltese flag.
Mr Pumpyansky, who is currently under UK and EU sanctions, owns steel group TMK. The UK imposed sanctions on hundreds of Russian citizens and entities last week, enabling authorities to freeze their assets.
Refinitiv data shows the 72-metre vessel is owned by a British Virgin Islands holding company called Pyrene investments, Reuters reported. An article published by the International Consortium of Investigative Journalists as part of the Panama Papers leaks names Pumpyansky as a beneficiary of the holding.
Forbes and specialist publication Superyacht Fan also list him as the Axioma's owner.
The Gibraltar government confirmed that the Axioma had arrived in port after asking permission to enter and "was confirmed to be the subject of an arrest action by a leading international bank in the Supreme Court of Gibraltar".
"The vessel is now subject to arrest by the Admiralty Marshal until further order," it said, without specifying the legal claims from creditors against the vessel or the vessel's owner.
Refinitiv shipping data showed the Axioma left the Caribbean island of Antigua on February 27 and spent the past three weeks crossing the Atlantic before reaching Gibraltar.
Earlier on Monday, a vessel linked to Roman Abramovich, the sanctioned owner of Chelsea football club, docked in the seaside city of Bodrum in south-west Turkey. A second superyacht linked to Mr Abramovich was spotted approaching the Turkish coast on Tuesday.