(CNN) -- The family of Bob Levinson, who disappeared from Iran seven years ago, has long known he worked for the CIA -- a fact they once feared disclosing because the U.S. government told them it could put Levinson in even more jeopardy. Now, they believe it could be the key to bringing him home. Members of Levinson's family offered the revelation in an interview with CNN on Tuesday, in which they accused the U.S. government of failing to do enough to find and free the missing American and prodded it to act before it's too late. The family said it's time for the government to lay out the facts about Levinson's case.
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U.S. government has failed to do enough to free him, Bob Levinson's family says
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Family says documents strongly suggest Iranian officials arrested him
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The family want U.S. to acknowledge Levinson's work with CIA; officials have not
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Being up-front "would be more of a positive step to getting him home," son says
We've said clearly that we have no knowledge of his whereabouts... We need the United States to explain for @placeholder what a CIA operative was doing, if he was ever in Iranian territory, what was he doing in Iranian territory."