Nuclear scientist Mohsen Fakhrizadeh was believed to be the leader of the Iranian nuclear programme. He was assassinated on Friday and Tehran was quick to point the finger at Israel. In response to the killing of Iran’s top nuclear scientist the country’s supreme leader, Ayatollah Ali Khamenei, said Iranian officials must take up the task of “pursuing this crime and punishing its perpetrators and those who commanded it”.
The killing will complicate the efforts of Joe Biden to find a solution to the Iran nuclear deal that Mr Trump abandoned.
The pact agreed between Iran and major world powers was agreed in 2015 under the Obama administration.
Mr Fakhrizadeh was killed on Friday when he was ambushed near Tehran.
His car was sprayed with bullets by special operatives.
The scientist was rushed to hospital where he later died.
Iran’s president Hassan Rouhani said his government would respond “at the proper time”.
On a televised speech he added: “Once again, the evil hands of Global Arrogance and the Zionist mercenaries were stained with the blood of an Iranian son.”
Israel declined to officially make a statement on the killing.
Israeli cabinet minister Tzachi Hanegbi said he did not know who carried out the assassination.
Speaking to Israeli news N12 ‘Meet the Press’, he said: “I have no clue who did it.
“It’s not that my lips are sealed because I’m being responsible.
“I simply really have no clue.”
Israeli embassies worldwide have now been put on high alert.
However, there have been no reports yet of concrete threats.
Israeli prime minister Benjamin Netanyahu’s office has declined to comment on the killing.
The US State Department and CIA have also declined to comment on the killing.