Iran's state-run television was apparently hacked on air Saturday, with a news bulletin interrupted by a protest against the country's supreme leader Ali Khamenei.
A mask appeared on the screen, followed by an image of Ali Khamenei with flames around him. The group called itself "Adalat Ali", or Ali's Justice, reports BBC.
The hacking comes after at least three people were shot dead when protesters clashed with security forces in new unrest over the death of Mahsa Amini.
Saturday's TV news bulletin was interrupted at about 18:00 local time with images which included Iran's supreme leader with a target on his head, photos of Amini and three other women killed in recent protests.
One of the captions read "join us and rise up", whilst another said "our youths' blood is dripping off your paws".
The interruption lasted only a few seconds before being cut off.
Such displays of rebellion against Ayatollah Ali Khamenei are historically rare, and he wields almost complete power within Iran. But following Ms Amini's death, there has been some open dissent.
Mahsa Amini was detained in Tehran by morality police for allegedly not covering her hair properly. The 22-year-old Iranian Kurd died in custody on 16 September, three days after her arrest.
Her death has sparked an unprecedented wave of protest across Iran.
Bd-pratidin English/Golam Rosul