TEHRAN, Iran — An Iranian nuclear scientist who disappeared a year ago was on his way home to Tehran today from the United States, ending a bizarre and mysterious intelligence drama.

Shahram Amiri said in an interview aired today on Iranian state TV that he was abducted by American and Saudi agents while on a pilgrimage to Saudi Arabia last year, drugged, whisked to the United States, where the CIA sought to force and bribe him into exposing Iranian secrets.

The U.S. has denied claims of an abduction and has depicted Amiri as a willing defector who changed his mind, apparently because he missed – or feared for – his family, still in Iran. On Tuesday, Secretary of State Hillary Rodham Clinton said Amiri had been in the United States “of his own free will and he is free to go.”

That was the Obama administration’s first acknowledgment that Amiri was even in the country since he vanished in Saudi Arabia in June 2009, fueling speculation that he had defected and was offering information on Iran’s nuclear program. The United States and its allies accuse Tehran of seeking to build a nuclear weapon, a claim Iran denies, saying its program is for peaceful purposes.

Whatever happened, Amiri’s case turned into a bizarre spiral last month, when Iranian state TV aired a video he purportedly made from an Internet cafe in Tucson, Arizona, and sent to Iranian intelligence claiming U.S. and Saudi “terror and kidnap teams” snatched him. In another, professionally produced one, he said he was happily studying for a doctorate in the United States. In a third, shaky piece of footage, Amiri claimed to have escaped from U.S. agents in Virgnia and insisted the second video was “a complete lie” that the Americans put out.

On Monday evening, he appeared at the Pakistani Embassy in Washington, asking to be sent home.

“I expect they got to his family,” said Clare Lopez, senior fellow at the Center for Security Policy and a former operations officer for the CIA. “Now he’ll go back and save them.” ABC News reported that Amiri called home this year because he missed his wife and son in Iran and that his son had been threatened with harm.

A U.S. official who was briefed on the case said Amiri, 32, had “left his family behind, that was his choice.” The official spoke on the condition of anonymity because the official was not authorized to speak publicly about the case.

Also unknown is what information of value, if anything, Amiri shared with American intelligence about the Iranian nuclear program. Before he disappeared, Amiri worked at Tehran’s Malek Ashtar University, an institution closely connected to the country’s powerful Revolutionary Guard.

State Department spokesman P.J. Crowley said he does not know what Amiri may have told U.S. officials, but that the U.S. government “maintained contact with him” during his stay in the United States. Pressed whether Amiri was a defector, Crowley replied, “I just don’t know the answer.”

Iran’s state Press TV today aired an interview with Amiri from a day earlier in which he elaborated on his alleged abduction. He said he was in the Saudi holy city of Medina when three men in a van posing as fellow pilgrims offered him a ride. “As I sat down, the man in back held a gun towards me and told me to keep quiet,” he said. “They took me to a secret place and injected me, and when I woke up I saw myself in a huge airplane” and was taken to America.

There, CIA agents “pressured me to help with their propaganda against Iran,” he said, including offering him up to $10 million to talk to U.S. media and claim to have documents on a laptop against Iran. “I promised myself that I wouldn’t talk against my country at all,” Amiri told Press TV.

He said the agents settled him in Tucson, suggesting he had relative freedom there on the condition “I not talk about my abduction or what happened afterward.”

But after they discovered he had made the first video, in April, “they relocated me from Tucson to Virginia with guards all around me and until this moment I’ve been monitored by armed agents.”

“They put more psychologial pressure on me. They told me they would kill me … They threatened me every time,” Amiri said.

Amiri’s video from Tucson, in which he is seen speaking into what seems to be a Web cam, was aired on Iranian TV on June 7. Hours later, another more professional one appeared on YouTube. In it, Amiri, wearing a sports jacket and sitting in an office, says into the camera that he is free, safe and working on his degree in the United States. But he gives no explanation for why he would apparently move to the U.S. from his pilgrimage without telling his family.

Yet another video appeared on Iranian TV on June 29. It shows Amiri saying the date is June 14.

“I have succeeded in escaping from American intelligence in Virginia,” he said, adding that he was speaking from a “safe place” although he feared he could be rearrested.

Iran’s Foreign Ministry said today that Amiri was on a flight home, traveling through the Gulf nation of Qatar and was expected to arrive in Tehran early Thursday. A U.S. official confirmed that Amiri left the United States Tuesday night, but couldn’t provide more details. The official spoke on condition of anonymity because of the sensitive nature of the case.

Deputy Iranian Foreign Minister Hassan Qashqavi told state TV that Iran will pursue the case of Amiri’s abduction through legal means.

Michael Rubin, an Iran expert at the American Enterprise Institute, said he expects Iran to reap propaganda value from Amiri’s return.

“What will happen now, however, is that the Iranians will score propaganda points, they will be able to televise a confession that may be more fiction than reality, but which regardless the CIA will have trouble refuting,” Rubin said.