This photo released by the semi-official Fars News Agency shows the scene where Mohsen Fakhrizadeh was killed in Absard, a small city just east of the capital, Tehran, Iran, Nov 27, 2020. (FARS NEWS AGENCY VIA AP)

TEHRAN - Iranian high-ranking nuclear physicist Mohsen Fakhri Zadeh was assassinated near capital Tehran on Friday by "armed terrorists," Iran's Ministry of Defense announced.

Local media reported that Fakhri Zadeh, head of the defense ministry's nuclear program, was attacked in the afternoon in Absard village, 60 km northeast of Tehran.

Iran’s UN envoy, Majid Takht Ravanchi, said in a letter to Guterres that Tehran “reserves its rights to take all necessary measures” to defend itself

Eyewitnesses said a blast occurred when the scientist's vehicle was traveling on a street of the village, then a shooting took place where several people were killed.

In the aftermath, there was a heavy presence of security forces stopping cars in Tehran in an apparent search for the killers, witnesses said.

The scientist was severely injured and taken to a hospital, but the medical team failed to rescue him, the ministry added. 

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UN Secretary-General Antonio Guterres urged restraint to avoid an escalation of tensions, his spokesman said.

Iran’s UN envoy, Majid Takht Ravanchi, said in a letter to Guterres that Tehran “reserves its rights to take all necessary measures” to defend itself. He also called on the UN Security Council to condemn the killing and take steps “against its perpetrators.”

With Reuters inputs