COLUMBUS, Ohio — The long-running case of a former deep-sea treasure hunter marking his sixth year in jail for refusing to disclose the whereabouts of missing gold coins has hit yet another roadblock.

Research scientist Tommy Thompson has been held in contempt of court since Dec. 15, 2015, for that refusal. He is also incurring a daily fine of $1,000. A hearing held Monday in hopes of helping draw the case to a conclusion ended with a federal judge giving Thompson two months to find a new attorney ahead of yet another hearing.

Thompson's case dates to his discovery of the S.S. Central America, known as the Ship of Gold, in 1988. The gold rush-era ship sank in a hurricane off South Carolina in 1857 with thousands of pounds of gold aboard, contributing to an economic panic.

Despite an investors lawsuit and a federal court order, Thompson, 69, still won't cooperate with authorities trying to find 500 coins minted from some of the gold, according to court records, federal prosecutors and Algenon Marbley, the judge who found Thompson in contempt.

Tommy Thompson marks 6 years in jail

Thompson has previously said, without providing details, that the coins — valued at about $2.5 million — were turned over to a trust in Belize. After Thompson failed to appear for a 2012 Ohio hearing to discuss the coins, U.S. marshals eventually tracked him to Florida in 2015 and arrested him.

Tommy Thompson refuses to disclose the whereabouts of 500 missing gold coins found in the historic shipwreck of the S.S. Central America. (AP)

Tommy Thompson refuses to disclose the whereabouts of 500 missing gold coins found in the historic shipwreck of the S.S. Central America. (AP) (Delaware County Sheriff's Office via AP, File)

Thompson pleaded guilty in April 2015 to skipping that hearing and was sentenced to two years in prison and a $250,000 fine. But his criminal sentence has been delayed until the issue of the gold coins is resolved.

Thompson, who has gone through several attorneys, is currently housed in a federal detention center in Milan, Michigan. Thompson told Marbley on Monday that he's having trouble finding a secure phone or computer connection to discuss his case with potential attorneys. A message seeking comment was left with the facility.

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Thompson also said he continues to suffer the effects of systemic exertional intolerance disease, also known as myalgic encephalomyelitis or chronic fatigue syndrome, which also affects his short-term memory.

"It’s hard to explain the number of roadblocks," Thompson said. "I don’t rest on my laurels; I’m working all the time here. It’s hard to communicate here."

Marbley gave Thompson until March 21 to find an attorney to argue pending motions Thompson has made, including for compassionate release because of concerns about the spread of the coronavirus behind bars.

"None of us wants this matter to drag on interminably," Marbley said.

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Federal law generally limits jail time for contempt of court to 18 months. But a federal appeals court in 2019 rejected Thompson’s argument that that law applies to him, saying his refusal violates conditions of a plea agreement.

On Jan. 14, the largest S.S. Central America ingot ever offered at auction, an 866.19-ounce find known as a Justh & Hunter ingot, sold for $2.16 million through Dallas-based Heritage Auctions.