Iran's president Hassan Rouhani on Saturday accused Israel of killing a prominent Iranian scientist long suspected by the West of masterminding a secret nuclear bomb programme, state TV reported.
"Once again, the evil hands of global arrogance were stained with the blood of the mercenary usurper Zionist regime," a term for Israel, Rouhani said in a statement, according to state TV.
"The assassination of martyr (Mohsen) Fakhrizadeh shows our enemies' despair and the depth of their hatred... His martyrdom will not slow down our achievements."
Fakhrizadeh died in hospital from wounds suffered during an attack by "armed terrorists" on Friday, the country's defense ministry has confirmed.
He was "seriously wounded" when assailants targeted his car before being engaged in a gunfight with his security team, the statement said.
It added that Fakhrizadeh, who headed the defense ministry's research and innovation organization, was later "martyred" after medics failed to revive him.
Iran's foreign minister, Mohammad Javad Zarif, has claimed there were reasons to believe Israel was involved in the assassination, while implying the killing had the blessing of the departing U.S. President Donald Trump.
"Terrorists murdered an eminent Iranian scientist today. This cowardice – with serious indications of [an] Israeli role – shows desperate warmongering of [the] perpetrators," Zarif wrote on Twitter.
He also called on the international community to "end their shameful double standards and condemn this act of state terror."
The military adviser to Supreme Leader Ayatollah Ali Khamenei vowed to "strike as thunder at the killers of this oppressed martyr."
"In the last days of the political life of their ... ally (Trump), the Zionists seek to intensify pressure on Iran and create a full-blown war," Hossein Dehghan tweeted.
Channels of the Telegram encrypted messaging app, believed to be close to Iran's elite Revolutionary Guards, reported that the top security body, the Supreme National Security Council, convened an emergency meeting with senior military commanders present.
Israel declined to comment. The White House, Pentagon, U.S. State Department and CIA also declined to comment, as did President-elect Joe Biden's transition team.
Fakhrizadeh has long been described by the United Nations and Israel as a leader of a covert atomic bomb program halted in 2003. Iran denied seeking to weaponize nuclear energy.
"Unfortunately, the medical team did not succeed in reviving [Fakhrizadeh], and a few minutes ago, this manager and scientist achieved the high status of martyrdom after years of effort and struggle," Iran's armed forces said in a statement carried by state media.
The semi-official news agency Tasnim said earlier that "terrorists blew up another car" before firing on a vehicle carrying Fakhrizadeh and his bodyguards in an ambush outside the capital Tehran.
Fakhrizadeh has the distinction of being the only Iranian scientist named in the International Atomic Energy Agency's 2015 "final assessment" of open questions about Iran's nuclear program and whether it was aimed at developing a nuclear bomb.
UN calls for avoiding escalation
A United Nations spokesperson on Friday called for exercising restraint and avoiding escalation in the Middle East region following the assassination of Fakhrizadeh.
"We have noted the reports that an Iranian nuclear scientist has been assassinated near Tehran today. We urge restraint and the need to avoid any actions that could lead to an escalation of tensions in the region," Farhan Haq, deputy spokesperson for UN Secretary-General Antonio Guterres, said when responding to a question related to the assassination.
In a letter to Guterres and Inga Rhonda King, president of the Security Council for the month of November, Iran's permanent representative to the United Nations Majid Takht Ravanchi expressed strong condemnation against the "criminal assassination" of its nuclear scientist.
He added Iran "expects the secretary-general of the United Nations and the Security Council to strongly condemn this inhumane terrorist act and take necessary measures against its perpetrators."
