Iran said today it has proof that the United States was behind the assassination of an Iranian nuclear scientist this week in Tehran. The IRNA state news agency said Iran's Foreign Ministry has sent a diplomatic letter to the US asserting that it has "evidence and reliable information" that the CIA provided "guidance, support and planning" to assassins "directly involved" in the killing of Mostafa Ahmadi Roshan.
IRNA also reported that Iran delivered a letter to Britain accusing London of having an "obvious role" in the killing. It said that a series of assassinations began after British intelligence chief John Sawers hinted in 2010 at intelligence operations against the Islamic Republic. The killing has sparked outrage in Iran, and state TV broadcast footage today of hundreds of students marching in Tehran to condemn Roshan's death and calling for the continuation of the country's nuclear program. (Read more Iranian nuclear program stories.)