Disturbing photos of Robert Levinson, the FBI agent who went missing in Iran in 2007, were released by his family on Tuesday.
Levinson is pictured wearing a Guantanamo Bay prisoners' uniform and a bushy grey beard, holding up signs that read "Help me" and "This is the result of serving 30 years for the USA."
The photos were sent to the family in April 2011, but the missing agent's wife released them this week because she feels that the effort to bring her husband home has not been concerted enough, according to Business Insider.
“When we received them, they were simply photographs with no indication of what purpose they served, and so there was no reason to put them out there because they didn’t do anything to help us resolve this case,” Christine said in an interview with Radio Free Europe. “That was the last time we had any information about Bob from anyone.”
Investigators were unable to trace the source of the photos, the Daily Mail reported. They are believed to have been taken two years ago, around the same time that a "proof-of-life" video of Levinson was released.
The careful procedure -- or tradecraft in spy talk -- that the perpetrators used to get the images to Levinson's family without leaving any other trace was simply too good to be an amateur job, intelligence officials said.
Though US officials initially believed that terrorists were responsible for Levinson's abduction, they have since shifted their suspicions to Iran's government. But Iranian officials have repeatedly denied knowledge of the specifics of Levinson’s disappearance or his current location, the New York Times reported.
"He's been held for a long time now," said CBS News' John Miller, who was FBI Deputy Director when Levinson went missing. "When they feel that the case is becoming on the back burner of discussions ... the family will stir the pot."
He added that the photographs are "taunting at the US" and serve as "a piece of propaganda that's really saying to the US, 'Negotiate, put something on the table, take a step forward, I'm stuck here.'"
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