This week marks the 40th anniversary of the beginning of the Iran hostage crisis. It was on Nov. 4, 1979, that revolutionary Iranian students breached the walls of the U.S. Embassy in Tehran, taking diplomats hostage, and ultimately holding 52 of them for the next 444 days.

While the ordeal for the embassy hostages is now in the distant past, for some Americans the nightmare continues. Among them is the family of Robert Levinson, a former FBI agent who was detained on Iran’s Kish island on March 9, 2007.

Yet now a tantalizing clue offers hope of a shift in his case.

Alluding to the hostages taken in 1979, the Levinson family issued a statement on Monday that noted: “Bob Levinson has been held more than 10 times longer — for 4,624 days. Bob Levinson must come home, and Iran’s hostage-taking as government policy must end.”

He is considered to be the longest-held hostage in U.S. history.

Even though there has been no news of Levinson’s whereabouts or well-being since a photo released in 2011, his family says they have every reason to believe he is alive. Now we have received a hint from the Iranian authorities that those hopes might be justified.

Seeking answers and justice, Levinson’s family filed a complaint with the United Nations Working Group on Enforced or Involuntary Disappearances in 2016.

At the time of filing, they were told that they should not expect Iran to acknowledge the inquiry, as they have generally ignored such cases. To the family’s surprise, though, last month they were informed that Iranian authorities had in fact responded.

In an email updating the family about the case, the U.N. agency noted that “According to the statement of Tehran’s Justice Department, Mr. Robert Alan Levinson has an on going case in the Public Prosecution and Revolutionary Court of Tehran.”

This is potentially huge news. It’s the first indication in over a decade from Iran that he may be in their custody and that authorities are pursuing a case against him.

“If they have charges against him, what are they?” wonders Sarah Moriarty, one of Levinson’s daughters.

For years Iran had publicly claimed to have no knowledge of Levinson’s fate, despite the fact that Iranian state news outlets reported he had been arrested at the time of his disappearance.

On Monday, the U.S. government announced a $20 million reward for information leading to the location, recovery and safe return of Levinson. That comes on top of a $5 million FBI award.

The combined $25 million in reward money is the highest ever of its kind, putting Levinson’s release on par with the capture of Islamic State leader Abu Bakr al-Baghdadi. Until the operation that led to his death last month in Syria, al-Baghdadi had been the most-wanted terrorist in the world.

Secretary of State Mike Pompeo spoke at an event to commemorate the dark anniversary of the 1979 hostage crisis. In attendance were some of the surviving hostages, other Americans who have since been held in Iran, and several loved ones of those still detained and missing inside the Islamic republic. Among them was one of Levinson’s sons, Douglas.

After a decade in which the U.S. government showed little evidence of working to free Levinson, his family believes that the Trump administration has made the safe return of Levinson a priority.

“We’re encouraged. This administration is engaged and completely committed to bringing my dad home,” Moriarty told me. “They’ve taken it as a personal mission. I think they care passionately about bringing my dad and other Americans home.”

In addition to Levinson, Iranian authorities are also holding at least four other Americans in detention.

“The Trump administration has made clear that the regime in Iran must release all missing and wrongfully detained Americans, including Robert Levinson, Xiyue Wang, Siamak Namazi and others,” Pompeo said at the event. “We will not rest until they are reunited with their families.”

It’s essential that the fate of these Americans remains a top priority. For all their sake, let’s hope the Trump administration is doing everything in its power to ensure that Iran frees them all very soon.

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