MADRID(BullionStreet) : Nearly five years after its discovery, Spain got back 17 tons of silver and gold coins scooped up from Spanish warship Nuestra Senora de las Mercedes, that sank during a 1804 gunbattle off the Straits of Gibraltar.

Odyssey Marine Exploration, a deep-sea treasure-hunting firm based in Tampa, Florida, discovered the shipwrecked treasure in international waters.

British warships had sunk it as it approached Spain as part of a fleet that had traveled from South America.

The treasure worth around $500 million was carried onboard two military planes was transported to a safe location in Madrid, reports said.

Soon after the March 2007 discovery, Spain laid claim to the 17-ton coin hoard, demanding its return and sparking a near two-year legal battle.

International treaties generally hold that warships sunk in battle are protected from treasure seekers and the Spanish government successfully argued that it had never relinquished ownership of the ship or its contents.

A federal district court first ruled in 2009 that U.S. courts didn't have jurisdiction, and ordered the treasure returned.

Odyssey then lost every round in federal courts trying to hold on to the treasure, as the Spanish government painted them as modern-day pirates plundering the nation's cultural heritage.

The company has said in earnings statements that it has spent $2.6million salvaging, transporting, storing and conserving the treasure.

But it is not expected to receive any compensation from the Spanish government for recovering it because the European nation has maintained that the company should not have tried to do so in the first place.

Meanwhile, Spain said the coins are classified as national heritage and must stay inside that country where they will be exhibited in one or more Spanish museums.

It ruled out the idea of the treasure being sold to ease Spain's national debt in a country grappling with a 23 percent jobless rate and a stagnant economy.