Former CIA Director says assassination of Iranian scientist could inflame regional conflict

The renowned nuclear scientist was reportedly ambushed in his car by gunmen in the town of Absard, east of Tehran, the BBC reports. The President of Iran, Hassan Rouhani, has since blamed Israel for the murder and has said that Iran will retaliate at a time of his choosing.

Fakhrizadeh was the head of Iran's ministry of defense's research and innovation organization, and his killing could have many geopolitical implications.

Brennan tweeted his response to Fakhrizadeh's murder, calling it a criminal act and stating that it creates a risk for "lethal retaliation."

Brennan draws a distinction between these sorts of political assassination's and strikes against leaders of terrorist organizations which are not observed sovereign nations. He explains that if Fakhrizadeh was killed by a foreign government, it will set a bad precedent for similar future assassinations.

"Such an act of state-sponsored terrorism would be a flagrant violation of international law & encourage more governments to carry out lethal attacks against foreign officials," he tweeted.

UN Secretary-General António Guterres has urged for restraint in reaction to the murder of the scientist, the BBC reports.

A spokesperson from Germany's foreign office echoed the message of restraint, asking all parties to refrain from any steps that could lead to a further escalation of the situation".

"A few weeks before the new US administration takes office, it is important to preserve the scope for talks with Iran so that the dispute over Iran's nuclear programme can be resolved through negotiations," the spokesperson said in a statement.