The world greeted with jubilation, anger or trepidation the news Sunday that Iran's supreme leader Ayatollah Ali Khamenei had been killed in the US-Israeli strikes on the Islamic republic one day earlier.

- Music in Tehran -

Iranians took to the streets cheering with joy, setting off fireworks and playing celebratory music after reports of Khamenei's death, according to witnesses and video footage verified by AFP.

The celebrations in Tehran began shortly after 11:00 pm (1930 GMT), according to multiple witnesses and audio recordings.

People were not, however, coming out en masse to celebrate, according to social media.

Many Iranians were fearful after the deadly crackdown on mass anti-government protests in January.

- Mourning in Tehran -

The thousands who did gather in the centre of Iran's capital were instead mourning Khamenei's death, according to AFP journalists.

The mourners, dressed mostly in black and some crying, chanted "death to America" and "death to Israel" in Enghelab (Revolution) Square, with many waving Iran's flags and holding photos of Khamenei.

Iranian state television announced a 40-day mourning period and seven public holidays.

Iran's President Masoud Pezeshkian on Sunday branded Khamenei's killing a "declaration of war against Muslims" by Israel and the United States.

Iran's powerful Revolutionary Guards vowed earlier on Sunday to punish Khamenei's "murderers".

- 'Serious violation ' -

China said Sunday the killing was "a serious violation of Iran's sovereignty and security, a trampling on the aims and principles of the UN Charter and the basic norms of international relations".

"China firmly opposes and strongly condemns this," Beijing's foreign ministry statement added in a statement, calling for "immediate halting of military operations".

- 'Cynical violation' -

Russian President Vladimir Putin, a key ally of Tehran, on Sunday slammed Khamenei's killing as a "a cynical violation of all norms of human morality and international law".

In a letter to Pezeshkian published by the Kremlin, Putin also expressed his "deepest condolences for the assassination".

- 'Most evil' -

"Khamenei, one of the most evil people in History, is dead," US President Donald Trump said, announcing the killing on his Truth Social network late Saturday.

The killing "is the single greatest chance for the Iranian people to take back their country," Trump said.

- 'Cruel tyrant' -

Israeli Prime Minister Benjamin Netanyahu also called for Iranians to "overthrow the regime" after Khamenei's killing.

"For more than three and a half decades, this cruel tyrant has spread terror across the world while oppressing his own people, while working tirelessly and without pause on a plan to destroy Israel," he said in a televised statement.

- 'Irreparable chasm' -

Pope Leo XIV on Sunday called for an end to the "spiral of violence".

"Faced with the possibility of a tragedy of enormous proportions, I appeal to the parties involved to assume the moral responsibility to stop the spiral of violence before it becomes an irreparable chasm," the pope told a crowd in St Peter's Square.

- Deadly protests -

At least nine people were killed as hundreds of pro-Iranian protesters tried to storm the United States consulate in the Pakistan megacity of Karachi on Sunday, according to a hospital toll seen by AFP.

Hundreds of Iraqis also attempted Sunday to storm Baghdad's fortified Green Zone, where the US embassy is located, an AFP journalist reported.

Protests also took place in Srinagar, in Indian-administered Kashmir.

- 'Dustbin of history' -

The son of Iran's late shah on Saturday hailed the killing, saying the Islamic republic that replaced his pro-Western father was finished.

"With his death, the Islamic Republic has effectively come to an end and will soon be consigned to the dustbin of history," Reza Pahlavi wrote on X.

- 'Defining moment' -

EU foreign policy chief Kaja Kallas said Sunday that the killing was a "defining moment".

"What comes next is uncertain. But there is now an open path to a different Iran, one that its people may have greater freedom to shape," Kallas wrote on X.

- 'Few' will mourn -

UK Defence Secretary John Healey said on Sunday that "few people will mourn" Khamenei, echoing Australian Prime Minister Anthony Albanese.

Khamenei "was responsible for the regime's ballistic missile and nuclear programme, support for armed proxies and its brutal acts of violence and intimidation against its own people", Albanese told reporters.

French government spokeswoman Maud Bregeon likewise said that France "could only be satisfied with his demise", calling him a "bloodthirsty dictator".

- 'Free Iran' -

Jubilant Iranian-Americans on Saturday took to the streets from Boston to Los Angeles to cheer Khamenei's death.

In Los Angeles, home to a massive Iranian diaspora, singing and ululating marchers carried flags of shah-era Iran and posters bearing Trump's image, with some wearing "Free Iran" shirts.

- 'Gangster-like' -

North Korea condemned on Sunday the US-Israeli attack as an "illegal act of aggression".

Pyongyang said the military actions showed the "shameless and gangster-like conduct" of the two allies, who it said had chosen to "abuse military force to fulfil their selfish and hegemonic ambitions".

- 'Heinous' attack -

Iran's ally Hamas on Sunday mourned Khamenei. "The US and the fascist occupation government bear full responsibility for this blatant aggression and heinous crime," the Palestinian Islamist group said.

Fellow Iran proxy Hezbollah likewise vowed to "undertake our duty of confronting the aggression" of Israel and the US.

burs-st/sbk