A couple at Florida International University charged with being covert agents for the Castro government pleaded not guilty in Miami federal court.

BY JAY WEAVER

A pair of Florida International University employees pleaded not guilty Thursday at their arraignment in Miami federal court, and their lawyers later decried their detention in solitary confinement as pretrial punishment.

The couple are accused of operating as covert agents for Cuba's communist government for decades, using shortwave radios, numerical-code language and computer-encrypted files to send information about Miami's exile community to Cuban intelligence commanders.

Carlos M. Alvarez, 61, a tenured professor, and his wife, Elsa Prieto Alvarez, 55, a mental-health counselor, were denied bond on Jan. 9 by U.S. Magistrate Judge Andrea Simonton. The South Miami couple are charged with failing to register with the federal government as foreign agents.

If convicted, they face up to 10 years in prison.

FLIGHT RISKS

Last week, Simonton said she believed that the gravity of the charges against the Alvarezes, their past academic trips to Cuba and their contacts in Fidel Castro's government made them flight risks if they were released on bond.

Their attorneys, Steven Chaykin and Jane Moscowitz, said Thursday that ``their presumption of innocence has been eviscerated.''

This is not the first time at least one of their names has surfaced in official investigations into the Castro government's alleged spying in South Florida.

Congressional testimony by Florida Department of Law Enforcement agents in 1982 attempted to link Elsa Prieto Alvarez to the Antonio Maceo Brigade, founded in the 1970s by young Cuban exiles who often split with their parents and supported the Cuban revolution.

The agents said Elsa Alvarez had been identified as a member of the brigade by the Rev. Manuel Espinosa, a Hialeah preacher and self-proclaimed double agent, who died in 1987.

But on Thursday, her lawyer strongly denied that allegation.

''She was never a member of the Antonio Maceo Brigade,'' Moscowitz said.

Andres Gomez, the longtime brigade leader, told The Miami Herald that Elsa Alvarez was not a brigade member -- although he did not rule out that she may have attended a brigade meeting or taken a trip to Cuba with the brigade from some other U.S. city.

During the 1982 congressional testimony, the FDLE agents also warned the federal government that several Cuban exiles, including Elsa Alvarez, were providing sensitive information to Cuba's government just as Miami was struggling to absorb more than 125,000 Mariel refugees, hundreds of them prisoners with serious criminal backgrounds and patients with severe mental illnesses.

TESTIMONY

Testifying before a U.S. Senate subcommittee investigating Cuba-related terrorism in South Florida, Sergio Pinon, then an FDLE agent, accused Elsa Alvarez of sending along to Cuba private information on mentally ill patients at Jackson Memorial Hospital.

Moscowitz denied that her client had access to Jackson records or that she had passed along such information to Cuba.

The couple's attorneys sharply criticized their clients' detention before trial. They said they will appeal the denial of bond and challenge their solitary confinement in the Federal Detention Center in downtown Miami. The Alvarezes are on paid leave from their FIU jobs.

''We think they are being inappropriately detained,'' Chaykin, who represents Carlos Alvarez, said after the brief arraignment. ``They are being punished for a crime they were not convicted of.''

Moscowitz said it has been particularly hard for her client, Elsa Alvarez, to be separated from the couple's 12-year-old daughter. ''She is in distress,'' Moscowitz said. ``But somedays she is full of fire. She is ready to fight.''

Their indictment, which included no mention of top-secret U.S. government information being disclosed, came months after the couple's admission because of additional investigative work in the case, interim U.S. Attorney R. Alexander Acosta said.

Their confessions were videotaped this summer, according to one law enforcement source familiar with the case.

But the couple's attorneys dispute that claim. They said that some of Carlos Alvarez's statements may have been videotaped by the FBI, but that Elsa Alvarez's statements were not recorded in any way.

Miami Herald staff writer Alfonso Chardy contributed to this report.