 -- Until Saturday, the public had never heard of Nosratollah Khosravi-Roodsari, the American who elected to stay in Iran after his negotiated release this weekend.

Khosravi-Roodsari was never publicly reported being held in any Iranian prisons until after he was released in a historic prisoner exchange Saturday. Khosravi-Roodsari’s background and identity are now cloaked under a shroud of mystery.

In his remarks Sunday touting the exchange, President Obama glossed over Khosravi-Roodsari’s biography, only saying he, too, was “unjustly detained.”

“Two other Americans unjustly detained by Iran have also been released -- Nosratollah Khosravi-Roodsari and Matthew Trevithick, an Iranian -- who was in Iran as a student,” Obama said Sunday. “Their cases were largely unknown to the world, but when Americans are freed and reunited with their families, that’s something that we can all celebrate.”





Khosravi-Roodsari’s name does not appear anywhere on the Internet prior to Saturday’s announcement when the State Department named him and four other Americans involved in the swap. In the digital age of the 21st century, his anonymity online is an anomaly in itself.

So what was Khosravi-Roodsari doing in Iran? How long had the American been jailed? Why was he imprisoned?

“When it comes to Roodsari, privacy considerations preclude us form offering any more details,” one senior administration official noted in an email to ABC News this morning.

The State Department also declined to comment.

Given the exhaustive efforts the United States expended to win his freedom, Khosravi-Roodsari’s decision to stay in Iran rather than fly out with the others is also intriguing.

“It’s his free determination where he wants to go,” another senior administration official said during a background call with reporters on Sunday. “We don’t make that judgment for him.”