A fire at Iran's notorious Evin prison late on Saturday killed four detainees and injured 61, state media reported, as anti-government protests sparked by a woman's death in police custody continued on Sunday, including at several universities.
Iranian authorities said on Saturday that a prison workshop had been set on fire "after a fight among a number of prisoners convicted of financial crimes and theft". Evin holds many detainees facing security charges, including Iranians with dual nationality.
Iran's judiciary said four of those injured in Saturday's fire were in critical condition and that those killed had died of smoke inhalation, Iranian state media reported.
Earlier state television aired video apparently showing that calm had returned to the facility.
The protests sparked by 22-year-old Mahsa Amini's death while in the custody of Iran's morality police on Sept. 16 have turned into one of the boldest challenges to the clerical leadership since the 1979 revolution, and have been met with a brutal state crackdown.
Rights groups say at least 240 protesters have been killed, including 32 minors. The authorities have not published a death toll.
Protests continued at several universities on Sunday, including in the cities of Tabriz and Rasht, to a heavy deployment of riot police. Videos posted on social media showed students at a Tehran university chanting: "Iran has turned into a big prison. Evin prison has become a slaughterhouse."
Reuters could not independently verify the footage.
Families of some political detainees at Evin prison took to social media to call on the authorities to ensure their safety, which in 2018 was blacklisted by the U.S. government for "serious human rights abuses".
Footage of the prison aired on state television hours later showed firefighters inspecting a workshop with fire damage to the roof. It also showed inmates asleep in their wards.
Atena Daemi, a human rights activist, said that relatives of prisoners held in the women's section had gathered at the prison for routine visiting hours, but that the authorities had denied them access, resulting in a standoff.
The relatives were told that the prisoners were "fine, but the phones are broken", according to Daemi. However, she later tweeted that some women prisoners had called their families briefly.
A lawyer representing an American Iranian held at Evin, Siamak Namazi, imprisoned for nearly seven years on espionage-related charges rejected by Washington as baseless, said on Sunday that Namazi had contacted his relatives.
Several other dual national Iranians and foreign citizens are held in Evin prison mostly for security-related charges.
"I am pleased to report that #SiamakNamazi has now spoken to his family. He is safe and has been moved to a secure area of Evin Prison. We have no further details at this time," Jared Genser said in a tweet.
The husband of Iranian journalist Niloofar Hamedi, who broke the news of Amini's death and was arrested last month, also wrote on Twitter that she had telephoned him on Sunday.
The prison has long been criticised by Western rights groups. Human Rights Watch has accused authorities at the prison of using threats of torture and of indefinite imprisonment, as well as lengthy interrogations and denial of medical care for detainees.
A group of hackers calling themselves Edalat-e Ali (Ali's Justice) posted videos in August last year of leaked surveillance footage from Evin prison showing guards beating or mistreating inmates.
Some foreign governments whose citizens are being held in the prison have expressed concern.
