Hundreds of Iranian protesters have reportedly been killed, according to an independent group, as the regime threatened to retaliate if attacked by the US.
Details on the protests are scarce as a communications blackout is still in effect across Iran's 31 provinces, with demonstrations, which began at the end of December over a sharp decline in the value of the rial currency, continuing into their third week.
They have since transformed into the most significant challenge to the regime for several years.
Over the weekend, Tehran's prosecutor-general said those demonstrating will be tried as "enemies of god" - a charge punishable by the death penalty - and Donald Trump said the US is "ready to help" protesters.
Meanwhile, US foreign secretary Marco Rubio has discussed the situation - and the possibility of American intervention - with Israeli Prime Minister Benjamin Netanyahu.
Read more: Body bags show emerging picture of Iranian crackdown
According to the US-based Human Rights Activists News Agency, at least 544 people have now been killed during the disorder - up from 116 deaths recorded by the end of Saturday.
It added that it has also received 579 other reports of deaths that remain under investigation, which would bring the total to 1,123.
More than 10,681 individuals have also been transferred to prisons following arrest, the non-government organisation said.
It added in an update earlier on Sunday that most of the victims were killed by live ammunition or pellet gunfire, predominantly from close range.
State TV showed dozens of body bags on the ground at the coroner's office in Tehran, saying the dead were victims of events caused by "armed terrorists", as well as footage of people gathered outside the Kahrizak Forensic Medical Centre in the capital waiting to identify bodies.
Iranian president ready to listen to people
It comes after Iran's president, Masoud Pezeshkian, addressed the protests for the first time in an interview with regime-linked national media.
During the interview, he said "terrorists" linked to foreign powers were killing people, burning mosques and attacking public property, and that Iran's enemies were looking to "sow chaos and disorder" by "ordering riots".
However, Mr Pezeshkian said the Iranian establishment was ready to listen to its people, and that the government was determined to resolve people's economic problems.
He then urged citizens to distance themselves from "rioters and terrorists," who he said were trying to "destroy the entire society".
Speaker: US strikes would make bases 'legitimate targets'
Meanwhile, Mohammad Baqer Qalibaf, the speaker of the Iranian parliament, suggested the regime would retaliate against any US attack.
It followed Mr Trump's remarks on Friday that the US would hit Tehran "very hard" if the government "start[s] killing people", which the speaker said would make Israeli and regional US bases "legitimate targets".
While Mr Qalibaf was speaking, MPs in parliament shouted "Death to America!"
Citing an Israeli source, the Reuters news agency reported that Mr Netanyahu and Mr Rubio did discuss the possibility of a US intervention in Iran in a phone call on Saturday.
Read more:
Regime is more vulnerable than ever, but shows no sign of relenting
Everything you need to know about the Iran protests
Israel is now on high alert for a possible US intervention in Iran amid ongoing anti-government protests, three Israeli sources also told the news agency.
A US official confirmed only that the conversation took place, not its content.
Separately, the Israeli prime minister praised the "demonstrations for freedom," adding: "The people of Israel, and indeed the entire world, marvel at the immense bravery of the citizens of Iran.
"We all hope that the Persian nation will soon be freed from the yoke of tyranny."
(c) Sky News 2026: More than 500 killed in Iran, US rights group says, as president accuses 'ter

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