A woman who spent time in the same jail where a British mother is being held accused of plotting to overthrow the Iranian government has revealed the torture, sexual abuse and threats she endured as a teenager in the "black hole of evil".
Nazanin Zaghari-Ratcliffe is currently serving a five-year prison sentence after being arrested at Tehran airport in April 2016 as she attempted to return home from a visit to see her family.
She is being held at Evin Prison which Amnesty International has criticised for denying prisoners medical care and proper food, while human rights campaigners in Iran have described its curbs on visiting rights "cruel".
There is nothing to suggest she is being tortured, but ex-inmate Marina Nemat tells Sky News of the horrifying treatment she endured in the women's wing at the jail:
:: One day, I looked around me, and I had lost my freedom, my family, my religion, my name, and my dignity
Two members of Iran's Revolutionary Guard came for me on January 15, 1982, and arrested me at home in Tehran.
I was 16-years-old. It was about nine or 10 o'clock at night.
They put me in a car and drove me north to Evin Prison - a compound that has many buildings in a large area north of Tehran surrounded by tall brick walls, barbed wire, and guards with guns.
I was blindfolded upon arrival and taken in. They took me along hallway after hallway after hallway.
I couldn't see much, but I could see that there were many people sitting by the walls along the hallway.
I was told to sit on the floor and wait. It was very quiet.
Eventually, someone called my name, and I was taken for interrogation.
A door closed behind me and I was told to sit. I couldn't see the man questioning me because I was still blindfolded.
"Have you attended protest rallies against the government?" he asked.
I said I had. It was not some state secret. I went to rallies almost every day after school with my friends.
My parents knew, the principal knew, the shopkeepers knew. I didn't wear a ski mask on the streets of Tehran. What was the point of lying?
"Have you written articles against the Government?" he said.
"Yes, in my school newspaper."
He wanted to know the whereabouts of a girl who I hardly knew. I didn't know where she was.
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They took me to another room where they took off my blindfold. I was in a small room with two men: Ali and Hamehd.
There was a desk, two chairs, and a bare wooden bed.
They handcuffed me and noticed that my hands would easily slide out of the cuffs without much effort. I was about 6.4 stone (40.8kg).
They laughed and put both my wrists into one cuff, and, as it clicked, my right wrist cracked.
The torture had not even begun yet. I screamed. At that point, if the devil appeared and asked me to sell him my soul and he would return me home to my mum, I would.
I would have sold my soul with whipped cream and a cherry on top. I would have done anything to get out of that room.
They tied me to the bare wooden bed. I was lying down on my stomach. They lashed the soles of my feet with a length of cable that looked like a garden hose but was not hollow.
This is the most common method of torture in the Middle East. Why? Because our nerve ends are in our feet.
With every strike, my nervous system would explode, and then it was magically put back together again, and I was wide awake for the next.
A place beyond pain.
I began to count the strikes, but I forgot how to count. They eventually stopped beating me and made me sit up.
I looked at my feet, and I laughed out loud. My feet looked like overgrown party balloons with toes on them, indigo blue. I looked like a cartoon character. They thought I was resisting, so they beat me more.
Torture is not really designed to get information, because the tortured tells the torturer what he wants to hear; torture is designed to kill the human soul.
When they succeed, they stop. If they don't, then they will execute you.
And they are not trying to just kill your soul, they are trying to kill the soul of your family and your country and the world. This is why torture is a crime against humanity.
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I was sent to 246, a public women's cellblock in Evin, where I was with a few of my school friends and many other young women.
There was another form of torture in Evin. Sometimes girls were called for interrogation at midnight and they were returned to the cellblock at 5am with no visible torture signs.
If you knew the girl, you would go up to her and ask, "Where were you last night?"
And she would give you some lame excuse like, "They took me for interrogation and nothing happened".
Yeah, right. That didn't happen in Evin. But then she would give you the look that said, "Get lost. I don't want to talk about this". So you would respect your friend and go away.
They called me for interrogation about five months after my arrest. It was daytime. My interrogator Ali was there. He took off my blindfold and looked me straight in the eye.
"Listen carefully," he said.
"You had a death sentence for being an enemy of God. I reduced it to life in prison. You're going to be in prison forever and nobody cares.
"You'll become my wife, or I'll arrest your parents and your boyfriend."
I knew he was serious. I knew anything could happen in Evin.
If he arrested my parents, I wouldn't have a home to go back to.
"I'll do anything you ask. Just leave my family alone," I said. He told me I had to convert to Islam from Christianity. I did. He even changed my name.
One day, I looked around me, and I had lost my freedom, my family, my religion, my name, and my dignity.
How much more can you take away from a person?
I was being raped over and over again in solitary confinement in Evin at the age of 17, and it was absolutely legal. I couldn't even complain about it.
The conditions in Evin Prison have not changed a great deal since I was there in the 80s.
Torture and sexual abuse are still widely used. I have campaigned for the release of many Evin prisoners. Some of them have been released, but others are still there.
People ask me how and why I survived.
When I was stuck in a black hole of evil made by men, I needed to remember that even though it seemed that the world had forgotten my friends and me, there were still people out there who cared about us.
My cellmates helped me remember that. I was released in March 1984, more than two-years after my arrest.
I take this opportunity to remind Nazanin Ratcliffe, Saeed Malekpur, and other Evin prisoners that they are not forgotten.
We care. We're doing our best to make sure the world knows about their ordeal and does its best to bring them home.
Do not lose hope.
:: Marina Nemat was incarcerated in Evin Prison from 1982-1984 for her views against the Iranian Revolution. She escaped to Canada in 1991 and regularly speaks about her experiences to students as well as at the annual Oslo Freedom Forum. She has written in support of Nazanin Zaghari-Ratcliffe, but is not alleging the British mother has been tortured. Visit her website .