A former FBI agent missing for more than a month may be in the hands of Iranian authorities, according to an American fugitive assassin living in Iran.

Dawud Salahuddin, an American citizen who was granted asylum in Iran after admitting to the 1980 murder in Maryland of a former Iranian diplomat, told the Financial Times that he met retired FBI Agent Robert Levinson in a hotel on Kish Island on March 8, three days before he was reported missing on March 11.

Levinson's family has said he was at the Iranian resort to help with a film about the island, which is known for its beaches, turtles and liberal atmosphere.

While the FBI has stressed that Levinson is not working for the bureau, Salahuddin told the Financial Times that he met with Levinson to put him in touch with Iranian officials who might assist him in a cigarette-smuggling investigation he was conducting for a tobacco company.

“I don’t think he is missing, but don’t want to point my finger at anyone," Salahuddin told the Financial Times. "Some people know exactly where he is."

Levinson's responsibilities at the FBI included gathering intelligence on Russian criminal gangs.

The U.S. State Department last week formally asked Iran to investigate Levinson's disappearance. Iranian officials, fresh off the release of 15 captured British sailors and marines, reportedly said they would look into the case.

Some U.S. officials suspect Levinson is being held by Iran, the Financial Times reported, adding that European diplomats stop short of calling Levinson a “hostage” out of concern that it might escalate tensions between the U.S., Britain and Iran.