Four prisoners died in a fire that raged overnight in the Iranian capital's notorious Evin prison, said the judiciary in the Islamic republic which has been rocked by a month-long protest movement sparked by the death of Mahsa Amini.
"Four prisoners died due to smoke inhalation caused by the fire and 61 were injured," the judiciary authority's website Mizan Online reported, adding that four of the injured were in "serious condition".
Rights groups had voiced grave fears for the inmates after gunshots and explosions were heard during the blaze from inside the complex, illuminated by flames and smothered by smoke in video footage posted on social media channels.
The fire -- blamed on "riots and clashes" and later brought under control according to authorities -- came as Iran has been rocked by protests over the death of 22-year-old Amini after her arrest for violating Iran's strict dress code for women.
The demonstrations have turned into a major anti-government movement in the Islamic republic, confronting its clerical leadership with one of its biggest challenges since the ousting of the shah in 1979.
Evin, infamous for the ill-treatment of political prisoners, also holds foreign detainees and thousands facing criminal charges. Hundreds of those arrested during the recent demonstrations have reportedly been sent there.
"The life of every political and ordinary crime prisoner (in Evin) is at grave risk", the Oslo-based non-government group Iran Human Rights (IHR) warned overnight.
It said authorities had closed off roads leading to the prison in an apparent bid to stop protests taking place outside the jail.
But some headed there on foot and chants of "Death to the dictator" could be heard in videos shared by social media channel 1500tasvir.
"Prisoners, including political prisoners, are completely defenceless inside that prison," said Hadi Ghaemi of the New York-based Center for Human Rights in Iran (CHRI).
Freedom of expression group Article 19 said it had heard reports of telephone and Internet connections at Evin being cut.
Iranian rights activist Atena Daemi, herself a long-time inmate of Evin, wrote on Twitter that in the early hours of Sunday several buses and ambulances were seen leaving the prison.
'Fully responsible'
The judiciary's Mizan Online said late Saturday that the fire at the prison had been extinguished.
Citing a Tehran prosecutor, the official IRNA news agency said the clashes at Evin had "nothing to do with the recent unrest in the country".
The four inmates who died had been convicted of robbery, Mizan said.
Evin prison holds foreign inmates including French-Iranian academic Fariba Adelkhah and US citizen Siamak Namazi, whose family said he was taken back into custody this week after a temporary release.
Mr Namazi's US attorney Jared Genser said he had now spoken to his family and that he was unharmed.
Australian academic Kylie Moore-Gilbert, who was held in Evin for most of her 800-plus days behind bars in Iran, told AFP she had heard that all the women political prisoners were safe.
US State Department spokesman Ned Price said that Iran was "fully responsible for the safety of our wrongfully detained citizens".
Award-winning Iranian filmmaker Jafar Panahi and reformist politician Mostafa Tajzadeh are also among those believed to be held at Evin.
The prison has been dubbed "Evin University" because of the sheer number of intellectuals held there.
More sanctions loom
Rights groups reported night-time protests in Tehran in solidarity with Evin detainees, after angry demonstrators had rallied across Iran on Saturday despite internet cuts.
"Guns, tanks, fireworks; the mullahs must get lost," women without hijabs chanted at Tehran's Shariati Technical and Vocational College, in a video widely shared online.
Jeering protesters hurled projectiles at security forces in Hamedan city, west of Tehran, in footage verified by AFP, and protesters were also seen in the northwestern city of Ardabil in videos shared on Twitter.
At least 108 people have been killed in the Amini protests, and at least 93 more died in separate clashes in Zahedan, Sistan-Baluchestan province, according to IHR.
Amnesty International has slammed an "unrelenting brutal crackdown" that has included an "all-out attack on child protesters" leading to the deaths of at least 23 minors.
A Revolutionary Guards commander said Saturday that three Basij militia members had been killed and 850 wounded in Tehran since the start of the "sedition", IRNA said.
The crackdown has drawn international condemnation and sanctions against Iran from Britain, Canada and the United States.
The European Union has agreed to level new sanctions, a move expected to be endorsed by its foreign ministers Monday.
Iran on Sunday shrugged off recent criticism by US President Joe Biden.
"Iran is too strong for its will to be swayed by interference... by a politician tired of years of failure," foreign affairs spokesman Nasser Kanani wrote on Instagram.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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