BOSTON (AP) — A former U.S. Marine held in Russia for more than four years on disputed charges is gravely ill and at risk of dying, his family and advocates said Friday.

Robert Gilman, a 32-year-old teacher detained since 2022, has been in "a dissociative stupor" for 47 days due to the abuse he has suffered in prison, said Eric Lebson, chief strategy officer of Global Reach, an advocacy group representing the family. Since Tuesday, Gilman has had a high fever and high blood pressure.

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Lebson said he has been moved from a prison to a civilian hospital, where he is hooked up to a feeding tube and handcuffed to a bed. His mother flew to Russia a couple of weeks ago in an attempt to see him, Lebson said, but hospital officials denied the visit.

Gilman's lawyer Irina Brazhnikova told Russian news agency Interfax on Friday that Gilman is in a psychiatric ward of a civilian hospital, where he's been since early July. Brazhnikova said defense lawyers have not been able to visit their client, prompting her to lodge complaints to the local prosecutor's office, the local branch of the Federal Penitentiary Service, and to the prison hospital, where Gilman is registered.