Mohsen Fakhrizadeh, a nuclear scientist who has been suspected of leading Iran's nuclear weapons program, was shot and killed Friday while traveling in a vehicle east of Tehran, Iranian state media said. He was apparently taken to the hospital for treatment, but doctors were unable to save him. Fakhrizadeh has long been a top target of the Israeli intelligence service Mossad, and Iranian Foreign Minister Javad Zarif believes Jerusalem was behind the assassination, but a spokesperson for the Israeli military refused to comment. Iranian President Hassan Rouhani also blamed Israel and said Iran would respond at the "right time." Not much is known about Fakrizadeh, believed to be 59, but a 2007 CIA assessment said his role as a physics professor was likely a cover story, and it later became clear he was in charge of Iran's warhead development, The New York Times reports.

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