Hackers have disrupted Iranian state TV broadcasts to transmit messages from the country's exiled crown prince, calling on the military to "join the people", online video has revealed.
It comes as activists said almost 4,000 people have been killed in a crackdown by authorities on anti-government protests.
They fear the number will grow far higher as information leaks out of Iran, which is still gripped by the regime's decision to shut down the internet.
Read more: Iran's uprising explained
And the blackout could be made permanent, according to internet freedom watchdog FilterWatch.
Despite the blackout, video has emerged online showing that multiple channels from Islamic Republic of Iran Broadcasting, the country's state broadcaster, were airing clips of Crown Prince Reza Pahlavi.
The video showed two clips of him, then included footage of security forces and others in what appeared to be Iranian police uniforms.
It claimed without offering evidence that others had "laid down their weapons and swore an oath of allegiance to the people".
"This is a message to the army and security forces," one graphic read. "Don't point your weapons at the people. Join the nation for the freedom of Iran."
In the hacked broadcast, the crown prince said: "I have a special message for the military. You are the national army of Iran, not the Islamic Republic army.
"You have a duty to protect your own lives. You don't have much time left. Join the people as soon as possible."
A statement from his office acknowledged the disruption that showed the crown prince.
Semi-official Fars news agency quoted the state broadcaster, which acknowledged the signal in "some areas of the country was momentarily disrupted by an unknown source".
It did not discuss what had been aired.
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Mr Pahlavi, son of Shah Mohammad Reza Pahlavi, fled Iran before his father was forced out during the 1979 revolution.
On 8 January this year, he urged protesters on to the streets as Iranian authorities shut down the internet and drastically intensified their crackdown.
The Iranian Human Rights Activists News Agency (HRANA) reported that as of the end of Sunday, it had verified 3,919 people had been killed in Iran.
It said a further 8,949 deaths were still under investigation, that 2,109 people had been severely injured, and that 24,669 detainees had been confirmed.
Meanwhile, an Iranian official told Reuters on Sunday that authorities had verified at least 5,000 people had been killed, with around 500 being security officials.
The official blamed "terrorists and armed rioters" for killing "innocent Iranians," claimed that "the final toll is not expected to increase sharply," and alleged that "Israel and armed groups abroad" had supported demonstrators.
(c) Sky News 2026: Hackers target Iranian state TV as exiled crown prince tells military to 'join the people'
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