Iranian scientist Shahram Amiri attends a news conference at the Imam Khomini airport in Tehran July 15, 2010. Amiri, a nuclear scientist who says he was abducted by US agents, thanked Iranian authorities for returning him home on Thursday. (Xinhua/AFP Photo)

Iranian scientist Shahram Amiri flashes the victory sign as he arrives at the Imam Khomini airport in Tehran July 15, 2010. Amiri, an Iranian scientist who says he was abducted by US agents, thanked Iranian authorities for returning him home on Thursday. (Xinhua/AFP Photo)

Iranian scholar Shahram Amiri gestures to people as he arrived in Tehran, July 15, 2010. Shaharm Amiri, 32, who arrived in Tehran early in the morning, told a news conference that he was kidnapped by the CIA and the abduction was part of the US campaign to add political pressures to Iran. (Xinhua/Ahmad Halabisaz)

Iranian scientist Shahram Amiri (R) and his son Amir Hossein attend a news conference at the Imam Khomini airport in Tehran July 15, 2010. Amiri, an Iranian scientist who says he was abducted by US agents, thanked Iranian authorities for returning him home on Thursday. (Xinhua Photo)