Spain seizes U.S. treasure boat near Gibraltar

GIBRALTAR (Reuters) - Spanish police forcefully boarded a boat operated by a U.S. treasure hunting company on Thursday after it left the British possession of Gibraltar, a witness aboard the boat said.

Spain says the company, Odyssey Marine Exploration, has treasure that Madrid believes could have been retrieved from Spanish waters or from a Spanish galleon which sank in the Atlantic during the colonial period.

The Ocean Alert sailed from Gibraltar, on Spain's southern tip, on Thursday morning and was shadowed by a Spanish Guardia Civil patrol boat for five km (three miles) before it left Gibraltar waters and was forcefully boarded by four officers.

Ocean Alert had a Spanish lawyer on board and the boat's captain agreed to be escorted to the port of Algeciras.

The Ocean Alert is one of three vessels belonging to Odyssey which are subject to a search warrant issued by a Spanish court last month.

Odyssey Marine Exploration, a Florida-based treasure-hunting company, has said it legally recovered gold and silver coins worth an estimated $500 million from a colonial-era wreck code-named Black Swan at a location in the Atlantic Ocean that it refuses to disclose.

Spain suspects the company of illegally flying treasure to the United States.