The brother of Iranian Nobel Peace Prize winner Narges Mohammadi says he fears her life is in imminent danger after she suffered a suspected heart attack in prison in north-western Iran.

Hamidreza Mohammadi, who is based in Norway, told the BBC that the 53-year-old human rights activist was found unconscious in her bed by fellow inmates at Zanjan Prison last week.

She was taken to the prison infirmary but officials refused to transfer her to a hospital despite her history of heart and lung problems, he said. She also suffers from severe blood pressure fluctuations.

He demanded that she be released immediately for a thorough medical examination.

He also warned that strikes and explosions near the prison since the start of the US-Israeli war with Iran a month ago had only added to her stress.

"This war has had a terrible effect on prisoners in Iran. If the prison gets hit, if the prisoners need immediate medical attention, they will not get anything and their lives are in danger," he told the BBC's Newsday programme.

"It's been really difficult for her family... Her children have gone through a lot. Now they experience very uncertain time when they don't know even if in the future there will be any peace or if their mother is going to live or die."

Narges Mohammadi, the vice-president of the Defenders of Human Rights Center in Iran, was awarded the 2023 Nobel Peace Prize for her activism against female oppression in Iran and promoting human rights.

She has spent more than a decade of her life in prison. In 2021, she began serving a 13-year sentence on charges of committing "propaganda activity against the state" and "collusion against state security", which she denied.

In December 2024, she was given a temporary release from Tehran's notorious Evin prison on medical grounds.

She continued campaigning while undergoing treatment and was arrested in the north-eastern city of Mashhad last December after giving a speech at the memorial ceremony of a fellow human rights activist. Her family said she was taken to hospital after being beaten on the head and neck during the arrest.

A few weeks later, protests against Iran's clerical establishment swept across the country. At least 6,508 protesters were killed and 53,000 others arrested in an unprecedented crackdown by security forces on the unrest, according to the US-based Human Rights Activists News Agency (HRANA).

In early February, Mohammadi was sentenced by a Revolutionary Court in Mashhad to an additional seven-and-a-half years in prison after being convicted of "gathering and collusion" and "propaganda activities", her lawyer said.

She was transferred without warning the following week to Zanjan prison and has been allowed only limited communication with her family since then.

Last Sunday, her legal team and one family member were allowed to visit her in prison under heightened surveillance.

The Free Narges Coalition said in a statement on Tuesday that "her general health was extremely poor, and she appeared pale and weak with significant weight loss when brought to the visitation room by a prison nurse".

It then cited Mohammadi's cellmates as saying on 24 March that she had been "found unconscious in her bed with her eyes rolled back" and that this lasted for more than an hour. She was carried to the prison infirmary by fellow inmates, where medication was administered to restore her consciousness, the coalition added.

"Despite this medical emergency and evident indications of a heart attack, authorities refused to transfer Mohammadi to a hospital or allow her to visit a specialist."

Mohammadi also reported that she had suffered debilitating headaches, nausea and double vision since her violent arrest, and that bruises were still visible on her body, according to the coalition.

"According to the Iranian law, in wartime, when they [the authorities] cannot guarantee safety of the prisoners, especially prisoners who are not dangerous to society, they must be allowed to leave the prison until the war is over," Hamidreza Mohammadi said.

"But not only [have they not done] it, they have denied all the political prisoners any medical attention, and their excuse is 'it is wartime'. So our demand is that she immediately be released for a thorough medical examination.

"We know her medical history, we know that she has heart problems and pulmonary problems. She must be in a hospital."

In a separate development on Thursday, the daughter of the prominent Iranian human rights lawyer and Sakharov Prize winner Nasrin Sotoudeh said her mother had been arrested in Tehran.

Mehraveh Khandan wrote on Instagram that Sotoudeh, 62, had been detained "last night while she was home alone".

When relatives later went to the house, they found "electronic devices, including mum and dad's laptops and phones, had also been confiscated", she said.

Khandan added that she had had no contact with her mother since her arrest and that it was unclear which branch of the security forces was holding her.

Sotoudeh has been imprisoned several times in connection to her human rights work, which has included representing women arrested for removing their headscarves.

In 2018, she was sentenced to 38 years in prison and 148 lashes. She was released on medical grounds in 2021 due to a serious heart problem.

Her husband, human rights defender Reza Khandan, has been imprisoned since 2024.

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