Jonathan Pollard reportedly was hospitalized at a facility off his prison campus.
Israel radio and representatives of Pollard's wife reported Friday that Pollard was taken to a facility outside the Butner Federal Correctional Complex, the prison complex in North Carolina where he is serving a life sentence for spying for Israel.
Butner has a medical facility, suggesting Pollard had suffered an emergency condition that could not be treated by a conventional clinic, said Aaron Troodler, a spokesman for the campaign to release him.
Pollard, 57,apparently has since returned to the prison; an official at Butner told JTA on Friday that he was in his regular prison facility.
Pollard's wife Esther had yet to reach him since learning of his hospitalization, Troodler said, and she called on his supporters to pray for his recovery and health.
Pollard, who has been imprisoned since 1986, reportedly has suffered from a variety of illnesses.
"There are many reasons to release him," Troodler said. "This latest episode highlights how important the health factor is."