When Iranian nuclear physicist Ardeshir Hosseinpour was gassed to death in 2007, the finger of suspicion was immediately pointed at Israel. Now, his sister claims he was murdered by Iran s Revolutionary Guard (IRI) because he would not cooperate with its efforts to divert nuclear work from peaceful purposes to building an atomic bomb. If Mahboobeh Hosseinpour s account can be confirmed, it could affect the next round of nuclear negotiations between Iran and the P5+1, the five permanent members of the UN Security Council and Germany