From WaPo:

 

Iran says it executed nuclear scientist in US spy mystery - The Washington Post

 

TEHRAN, Iran — Iran executed a nuclear scientist who defected to the U.S. and returned to the Islamic Republic under mysterious circumstances a year later, an official said Sunday, acknowledging for the first time that the nation secretly detained, tried and convicted a man authorities once heralded as a hero.

 

Shahram Amiri vanished in 2009 while on a religious pilgrimage to Muslim holy sites in Saudi Arabia, only to reappear a year later in a series of contradictory online videos filmed in the U.S. He then walked into the Iranian interests section at the Pakistani Embassy in Washington and demanded to be sent home.

 

In interviews, Amiri described being kidnapped and held against his will by Saudi and American spies, while U.S. officials said he was to receive millions of dollars for his help in understanding Iran’s contested nuclear program.

 

...

 

Amiri’s case indirectly found its way back into the spotlight in the U.S. last year with the release of State Department emails sent and received by Clinton, now the Democratic presidential candidate.

 

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An email forwarded to Clinton by senior adviser Jake Sullivan on July 5, 2010 — just nine days before Amiri returned to Tehran — appears to reference the scientist.

So what did the email say about him?