The disappearance of a former senior Iranian defence official in Turkey a month ago has raised speculation that he has either defected, or been seized by the CIA or Israel's Mossad.
Retired General Alireza Asghari, who served as Iran's deputy defence minister for eight years until 2005, went missing in Istanbul on February 7 after arriving from Damascus and checking into a hotel.
There was no official Iranian comment on the affair until this week, when Foreign Minister Manoushehr Mottaki said Tehran had asked for information about him.
If Mr Asghari has gone over to the west, or been abducted, he could be a major source of information on Iran's nuclear programme and a host of other security matters. Before serving as deputy defence minister, he had been a general with the elite Revolutionary Guard.
Mr Asghari reportedly also knows about two other affairs, one of great interest to Israel and the other to the United States. According to Israeli sources, he was commander of the contingent serving in Lebanon in the 1980s as liaisons with Hezbollah when a downed Israeli navigator, Ron Arad, was sold by the Lebanese militia holding him to the Revolutionary Guard. Arad was never heard from again, and Israelis have long contended that the key to his fate lies in Iran.
An Israeli website dealing with intelligence matters, Debkafile, said the US CIA was interested in Mr Asghari because he was allegedly involved in the abduction of five US soldiers two months ago in Karbala, Iraq. The five were subsequently executed. Their seizure reportedly was ordered by Iran to obtain the release of Iranian Revolutionary Guard officers taken prisoner in Iraq by the Americans.