Tehran sent a diplomatic letter to US Saturday, claiming it has evidence that the CIA is responsible behind the assassination of Iranian nuclear scientist Mostafa Ahmadi-Roshan, the Associated Press reported.
"We have reliable documents and evidence that this terrorist act was planned, guided and supported by the CIA," Iran’s foreign ministry said in the letter.
Roshan, 32, was killed in broad daylight on Wednesday when a magnetic bomb was attached to his car during morning rush-hour in Tehran.
Roshan’s death marks the fifth time in two years that a scientist from Iran’s nuclear program has been targeted, according to the Guardian.
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"Iran's response will be a tormenting one for supporters of state terrorism," Iran’s Joint Armed Forces Staff spokesman, Massoud Jazayeri, said without elaboration. "Our enemies, especially America , Britain and the Zionist regime (Israel), have to be held responsible for their actions,”
The US has denied any involvement in the death of Roshan amid high tensions over Iran’s controversial nuclear program.
The IRNA state news agency said Iran has also sent a similar letter to Britain, claiming they had an “obvious role” in Roshan’s assassination.
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Jazayeri also accused the International Atomic Energy Agency of being involved, saying published a list of Iranian nuclear scientists and officials that "has provided the possibility of their identification and targeting by spy networks."
US President Barack Obama introduced new measures for 2012 against Iran in an attempt to bolster the economic sanctions.
“After years of international sanctions that had little impact on Iran, U.S. President Barack Obama signed new measures on New Year's Eve that, if fully implemented, would make it impossible for most countries to pay for Iranian oil...
The combined measures mean Iran may fail to sell all of the 2.6 million barrels a day of exports it relies on to feed its 74 million people. Even if it finds buyers, it will have to offer steep discounts, cutting into its desperately-needed revenue.”