The former head of the Central Intelligence Agency (CIA) John Brennan has traded Twitter barbs with Texas Senator Ted Cruz over the killing of a top scientist believed to be behind Iran’s nuclear program.

Brennan, who was director of the CIA between 2013 and 2017, condemned the shooting ambush of Mohsen Fakhrizadeh as a “criminal act” and “highly reckless”.

Fakhrizadeh, an officer in the Iranian Revolutionary Guard, was named as the director of Iran’s nuclear weapons project in 2018. Tehran, which has always insisted its nuclear program is for peaceful purposes, reacted with anger to the death and suggested Israeli involvement. Neither Israel nor the U.S. has commented on the incident thus far.

In a tweet on Friday, Brennan said that the killing “risks lethal retaliation & a new round of regional conflict.”

“Iranian leaders would be wise to wait for the return of responsible American leadership on the global stage & to resist the urge to respond against perceived culprits,” Brennan tweeted on Friday, suggesting that Tehran wait for President-elect Joe Biden to take office.

In a follow-up tweet, Brennan said that such an act of “state-sponsored terrorism” violates international law and encourages other governments to carry out lethal attacks against foreign officials.

However Cruz criticized Brennan, describing it as “bizarre” to see the ex-CIA chief “consistently side with Iranian zealots who chant ‘Death to America.’ And reflexively condemn Israel. Does Joe Biden agree?”

But Brennan hit back on Friday evening, tweeting that Cruz had mischaracterized his comment.

“Your lawless attitude & simple-minded approach to serious national security matters demonstrate that you are unworthy to represent the good people of Texas,” he tweeted.

He followed this up by tweeting that he had worked hard during his career for Israel’s security and to “counter Iran’s malign activities” adding, “aside from his tiresome rhetoric, what has Senator Cruz ever done?” Newsweek has contacted Cruz’s office for comment.

Fakhrizadeh’s death threatens to heighten Middle East tensions in the last months of President Donald Trump‘s presidency.

Iran has vowed to retaliate, with supreme leader Ayatollah Ali Khamenei saying in a Twitter post that Iranian officials would be “pursuing this crime and punishing its perpetrators and those who commanded it.”

Iran’s President Hassan Rouhani said that the Islamic republic “will respond in time to the assassination of Martyr Fakhrizadeh”.

“Once again, the evil hands of Global Arrogance and the Zionist mercenaries were stained with the blood of an Iranian son,” he said.

Ex-CIA director John Brennan
Ex-CIA director John Brennan testifies on Capitol Hill, May 23, 2017 in Washington, DC. He has criticized Sen Ted Cruz in a Twitter spat over the killing of an Iranian nuclear scientist.
Alex Wong/Getty Images

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