| Three videos of Shahram Amiri giving conflicting accounts of his circumstances emerged when he was in the US |
He was later buried. Amiri had been held at a secret location after returning from the US, where he said he had been forcibly taken by the CIA. Some reports say he had in-depth knowledge of Iran's nuclear programme.
Mr Amiri, who was born in 1977, went missing after taking a pilgrimage to Mecca in 2009. He surfaced in the US a year later saying he had been kidnapped and put under "intense psychological pressure to reveal sensitive information" by the CIA.
In a video recording - apparently made in the US - he said: "They took me to a house located somewhere that I didn't know. They gave me an anaesthetic injection."
In another video he claimed he had escaped from US custody. He returned to Tehran in 2010 to a hero's welcome.