Iran has reportedly executed nuclear scientist Shahram Amiri for "spying". A spokesperson for the Iranian judiciary Gholam-Hossein Mohseni-Eje'i on Sunday said Amiri was convicted of "provided the enemy with vital information of the country", referring to the United States, where he reportedly disappeared to in 2009, The Washington Post reported.

Mohseni-Eje'i added, "This person had obtained top secret information and established contacts with our number one sworn enemy, America, and passed on our country's most crucial intelligence to the enemy." However, did not reveal why details of his detention and trial were hidden over the past year, in addition to the information he allegedly shared with the US.

Amiri's family said on Sunday that he was executed at an unknown location earlier this week, according to The Guardian. Iran had carried out several hangings on Tuesday, AP reported, citing local media.

The scientist was an expert on radioactive isotopes at Malek Ashtar University in Tehran, which is affiliated to the country's Defence Ministry. Details of the circumstances surrounding his disappearance remain unclear. He went missing from Saudi Arabia in 2009 while on a pilgrimage to Mecca and suddenly reappeared in the US six months later. While Iran had accused the US of kidnapping Amiri, US said he had defected voluntarily.