This Image provided by the Federal Bureau of Investigation(FBI) shows a photo of former FBI agent Robert Levinson, who went missing on Kish Island, Iran, on March 9, 2007, shackled and holding a sign. The United States announced a $5 million increased reward March 9, 2015 for information leading to the return of Levinson, as it marked the eighth anniversary of his mysterious disappearance in Iran. The FBI had previously issued a $1 million reward for Levinson's return in 2012, five years after he went missing.    AFP PHOTO / HANDOUT / FBI                         == RESTRICTED TO EDITORIAL USE / MANDATORY CREDIT: "AFP PHOTO / HANDOUT / FBI "/ NO MARKETING / NO ADVERTISING CAMPAIGNS / NO A LA CARTE SALES / DISTRIBUTED AS A SERVICE TO CLIENTS == (Photo by -- / FBI / AFP)
Former FBI agent Robert Levinson went missing on Kish Island, Iran, on March 9, 2007. AFP

Wife of ex-FBI man held by Iran criticises US failures