Iran protester: 'They said if we didn't keep quiet, they would rape us'
"They put me on the ground, and an officer put his boot on my back. He kicked me in my stomach, tied my hands, picked me from my arms, and then pushed me into a van."
This is how 51-year-old Maryam, a protester arrested last week in central Tehran, described the moment Iranian security forces detained her.
Protests have spread across in Iran since the death on 16 September of Mahsa Amini, a 22-year-old woman who was detained by the morality police in the capital three days earlier for allegedly breaking strict hijab (headscarf) rules.
Police maintain that she collapsed at a detention centre after suffering a heart attack, but her family allege that officers beat her head with a baton and banged her head against one of their vehicles.
The protests sparked by her death, led mainly by women, began with demands to end the mandatory hijab laws. But they have now turned into nationwide demonstrations against Iran's leaders and the entire clerical establishment.
'Ruthless' commanders
Despite widespread internet disruption, videos of protesters being arrested by the Iranian security forces have continued to be published on social media.
"It is worse than what you see on these videos," said Maryam, which is not her real name.
"I heard one of their commanders ordering their soldiers to be ruthless. The female officers are [just] as horrible. One of them slapped me and called me an Israeli spy and a prostitute."
The BBC has seen videos in which commanders are seen ordering riot police officers to "not pity the protesters and shoot them".
Allow Twitter content?
Other videos verified by the BBC appear to show security forces shooting live ammunition at protesters and arresting those they can catch.
According to the state media, more than 40 people have been killed during the unrest. Human rights groups have reported a higher death toll.
The overall number of people who have been arrested has not been shared by the authorities. However, the chief prosecutor of Mazandaran, a province north of Tehran, said at least 450 protesters had been detained there alone. Human rights groups say thousands of protestors are being detained.
"I pushed a security officer back and tried to run away, but very soon, a second person and a third one arrived," said Sam, a young protester from a major city. "After a few seconds, more than 15 agents were beating me ruthlessly."
He added: "I felt the taste of the blood in my mouth and the strikes of an electric stun gun on my body. They put me on the ground, tied my arms behind my back, and tied my feet with my shoelaces.
"One of the soldiers kicked me in my left eye while taking me to [the place] where they kept the other detainees."
'Fearless' young girls
President Ebrahim Raisi has pledged to "deal decisively" with the protests, which have now spread to most of Iran's 31 provinces.
For many Iranians, Mr Raisi is associated with the mass executions of thousands of political prisoners in the 1980s, when he was one of four judges who sat on secret tribunals that condemned them to death.
"They put me and the other detainees on the floor of a bus on top of each other for an hour and a half," said Sam.
"I was thinking about Raisi's role in executing political prisoners, and for a moment I thought that they may execute me."
Mr Raisi has insisted that those executed in the 1980s were convicted in accordance with Iranian law. And while the president is ultimately in charge of the riot police and other law enforcement forces, there is no evidence that he has ordered them to kill people involved in this month's protests.
Maryam said that people detained alongside her continued to protest while they were being transferred to a major Islamic Revolution Guard Corps (IRGC) facility.
"There were other girls with me in the van, but they were much younger," she said. "When I saw them and their bravery, I gathered myself. They started helping me.
"They were shouting and making fun of the officers. This generation is different from my generation. They are fearless."
Photos and videos verified by the BBC showed the relatives of arrested protesters queuing in front of the infamous Evin Prison in northern Tehran. They were waiting to find out information about the detainees or submit documents to secure their release on bail.
One person told the BBC that authorities had warned them not to publicise their family member's arrest "or their situation would worsen".
But not everyone has been transferred to major detention centres. Many are being held in small police stations and IRGC facilities, many of which are unknown to the public.
"We were moved to a small police station. They were not ready to receive so many people," Maryam told the BBC. "They put at least 60 women, including me, in a small room. We were standing next to each other and couldn't sit or move.
"They said we could not use the bathroom, and that if we got hungry we could eat our stools.
"After almost a day, when we shouted and protested inside the room, they started threatening us that if we didn't keep quiet, they would rape us."
'Keeping spirits high'
Another woman arrested in one of Iran's southern cities told the BBC that female security officers had made threats of sexual assaults.
"The officer who was registering us in the detention centre asked for my name and called me a prostitute," Fereshteh, which is not her real name, said. "When I complained, she said that if I continued she would ask one of the brothers [male prison guards] to have his way with [me]."
Behzad, a protester who was held at a major detention facility in Tehran, said: "They kept more than 80 people in a tiny room. We were all furious and in pain."
"They confiscated our mobile phones and searched through our pictures, videos and messages to see if we had shared any news of the protest. If so, they [said they] were adding it to our files."
"The next morning, a judge came and met us. They dropped the charges and released most of the teenagers."
"But for the adults, the judge asked brief questions and decided our fate based on that short court session."
Behzad said about 10% of people he was detained alongside were released without charge, while the rest were freed on bail.
Allow Twitter content?
Another protester who was detained for two days in Tehran told the BBC that despite the "hostilities", younger detainees had tried to "keep their spirits high".
"I was with protesters who were under 25. Some had blood on their faces, but they were smiling, chatting, and joking.
"One of them asked me to smile and added: 'We are victorious because we are right.'"