Today marks eight years since former FBI agent Bob Levinson disappeared in Iran.

Levinson’s family claims he was on a CIA mission when he vanished. The Iranian government insists that it is not holding him.

Secretary of State John Kerry is calling on the Iranian government for help finding Levinson. Meanwhile, the FBI has increased the reward to $5 million for information leading to Levinson’s safe return.

Levinson’s wife Christine went “On The Record” last year to discuss her missing husband. She told Greta Van Susteren that Kerry said he’s working as hard as he can to bring Levinson home.

“It will never be enough until he is home,” Christine Levinson said. “The whole United States government should be working on this.”

Levinson was last seen in 2013 proof of life photos. Tomorrow is his 67th birthday.

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