By: AP via Scripps News Group , Jacob Gardenswartz

Russia has released an American military veteran who spent more than four years in prison under abusive conditions and was said to be gravely ill and at risk of dying, a group advocating for him said Tuesday.

Robert Gilman is on his way to a U.S. military hospital in Texas, where he will be medically and psychologically assessed and treated, said Eric Lebson, chief strategy officer of Global Reach, a group that's been working to free him and other American detainees abroad.

Gilman's family has flown to Texas to be with him, including his mother, who was in Russia attempting to see him at the hospital.

Gilman, a 32-year-old teacher detained since 2022, was initially handed a 3 1/2-year sentence in 2022 when he was convicted of beating a police officer after being taken off a train for causing a disturbance.

He was later convicted of attacking a prison inspector during a cell check, beating an investigator and assaulting a guard, and he was sentenced in October 2024 to eight years and one month.

His sentence was extended last year to 10 years after he was found guilty of assaulting prison guards. Before he was flown out of Russia, he had been in "a dissociative stupor" for 47 days due to the abuse he has suffered in prison, Lebson said.

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Gilman had been moved from a prison to a civilian hospital, where he was hooked up to a feeding tube and handcuffed to a bed. U.S. Sen. Edward Markey had called on Russia and the U.S. to work together to get the Massachusetts resident released.

Gilman was one of at least 8 Americans who remain in Russian custody after a series of high-profile prisoner exchanges with the U.S. in recent years.