TAMPA, Fla. (AP) — The legal battle between the Spanish government and Florida deep-sea explorers intensified Thursday with the company’s announcement that the estimated $500 million in treasure recovered last year could have come from the wreck of a Spanish galleon.

An attorney for the Spanish government said he would go “full speed ahead” with trying to force Odyssey Marine Exploration to give back the 17 tons of silver coins and other artifacts after the company publicly announced the name of the Nuestra Señora de las Mercedes y las Animas, which sank in the Atlantic southwest of Portugal in 1804.

The announcement confirmed what was already widely believed in Spain and elsewhere.

Still, Odyssey had fought to keep the suspected identity of the lucrative shipwreck secret, fearing others would plunder the site. And, company officials argued, they still don’t have conclusive proof that the wreck is the one they think it is.

But on Thursday, a federal magistrate judge ordered Odyssey to provide its “working hypothesis” regarding the identity of the shipwreck. The company followed with a news release naming the Spanish galleon as the suspected wreck to which it had sought exclusive salvage rights west of the Straits of Gibraltar. A customs form in the court file indicated the coins were raised from that general location and flown out of Gibraltar.

In the order, U.S. Magistrate Judge Mark Pizzo wrote that he “finds it unlikely that the public release of the information would ignite a ’treasure hunting free-for-all’ as Odyssey claims.”

Greg Stemm, CEO of the publicly traded company, lamented the judge’s decision.

“Experience has shown us how difficult it is to prevent unwarranted speculation about the identity and potential value of our finds once the possible identity of a site is made public,” Stemm said in the statement. “But we also respect the need to make sufficient information public to satisfy the requirement to alert potential claimants.”

Odyssey created an international stir when it announced in May the coins had been recovered and flown back to Tampa. Spain went to federal court claiming ownership of the treasure if it is in any way connected to the country’s national heritage.

James Goold, the Washington-based attorney for the Spanish government, has accused Odyssey officials of dragging their feet in turning over information about the shipwreck. Pizzo seemed to agree with that assessment, saying in the order that he finds the company’s “appeal for secrecy to be disingenuous and utterly without merit.”

Odyssey officials believe the court will award them the majority of the treasure as the salver. Spain is arguing that it should all be returned because it was never expressly abandoned.