Rumors about Levinson have circulated for years, with one account claiming he was locked up in a Tehran prison run by Iran’s paramilitary Revolutionary Guard and U.S. officials suggesting he may not be in Iran at all. Dawud Salahuddin, an American fugitive living in Iran who is wanted for the assassination of a former Iranian diplomat in Maryland in 1980, is the last known person to have seen Levinson before his disappearance. Iran has offered a series of contradictory statements about Levinson in the time since. It asked the U.N. group to close its investigation into Levinson in February, saying “no proof has been presented by the claimant in this case to prove the presence of the aforesaid in Iran’s detention centres.”