A hacker group is releasing surveillance footage from the very inside of Iran's notorious Evin prison in what seems to be an unprecedented cyberattack against the Islamic Republic's heavily guarded jail system.

The group identified as "Ali's Justice" has been releasing the videos since Sunday, promising to feed the media even more. The videos show moments of extreme abuse, with prisoners being severely beaten by guards and forcibly dragged on the floors. In one case, an inmate is seen using a broken mirror to cut his veins in self-harm or apparent suicide inside a common bathroom before being rescued by fellow prisoners. In another incident, which has particularly enraged Iranians on social media, a cleric is seen stepping over an inmate who is lying motionless in a doorway.

The first image released by the hackers seemed to be from inside the prison's surveillance command room, with the screens displaying the cyberattackers' message. "Evin prison is a stain of disgrace on Raisi's black turban and white beard," the message read, specifically targeting Ebrahim Raisi, Iran's former judiciary chief and current president.

Evin has been home to most of Iran's political prisoners as well as some Western nationals, including British-Iranian activist Nazanin Zaghari-Ratcliff, whom Iran has jailed on "espionage" and other charges.