Esha Momeni, an American student visiting Iran, has been arrested and held in solitary confinement in the notorious section 209 of Tehran’s Evin prison for daring to campaign for women’s rights.

Friends, who have had no contact with her since she was arrested more than a fortnight ago, fear that she will be tortured. Her computer and film footage were seized by intelligence officials and she has not been allowed any visits by her family or her lawyer.

Her arrest comes as the hard-line government of President Mahmoud Ahmadinejad has launched a crackdown on the One Million Signatures campaign, which fights for equal rights in a country where women are treated as second-class citizens.

Momeni, 28, who was born in America but brought up in Iran, returned to Tehran from her studies in the US two months ago to work on a documentary about Iranian feminists. She was making the film as part of her postgraduate course at California State University, Northridge.

The equal rights campaign, which aims to persuade a million Iranians to sign a petition to the Iranian parliament, has irritated the regime, already beset by falling oil prices, high unemployment and runaway inflation.

During her two-month stay in Tehran, Momeni’s activities appeared harmless. She joined women printing homemade leaflets in their flats and interviewed fellow campaigners.

Fearing arrest for “endangering the state”, the campaigners surreptitiously approach other women in parks and hand out leaflets explaining the unfairness of laws such as those giving a woman’s evidence in court only half the weight of a man’s, or automatically granting men custody of children in a divorce.

Momeni, who was born in Los Angeles but moved back to Tehran with her family in the early 1980s, was no firebrand, more interested in the arts than politics, say her friends.

Her life changed five years ago when she married a man whom Reza Momeni, her father, described as “a male chauvinist who had emotional problems”. After a bitter divorce she returned to California to study for her master’s degree. The experience seems to have convinced her to become a feminist activist and she began working with the campaign’s branch in California.

Last month police stopped her as she drove on the Modarres highway, Tehran’s main north-south route, supposedly for overtaking. She had planned to leave Iran two days later. Clearly worried, Momeni called Parvin Ardalan, founder of the Iranian women’s campaign, as she was being pulled over. “She was talking to me when they were telling her to stop and was asking me what to do,” Ardalan said. “When I called her 20 minutes later her mobile was switched off.” Through contacts, Ardalan confirmed her worst fears. “Later that day, I was informed that Esha’s house had been searched, documents seized and her computer had been confiscated. They told me she had been taken to section 209 of Evin prison,” she added. Momeni was allowed only one telephone call from prison, to her father. He said she sounded scared.

Ardalan vowed to carry on despite the crackdown. “It’s a long time since I slept with fear. I have none,” she told The Sunday Times at her cramped Tehran flat last week. “This movement will never stop, never, ever. It might have to slow down for a while but we will never stop.”

Earlier this year, with three other women’s rights campaigners, she was sentenced to six months in jail and is awaiting the outcome of her appeal. About 50 other campaigners have been imprisoned.

When Ardalan was awarded the Olof Palme prize for outstanding achievement last year she was banned from travelling to Sweden to receive it.

Amnesty International and Human Rights Watch have denounced Momeni’s arrest. Amnesty said she was “at risk of torture or other ill-treatment”. Former prisoners in section 209, which is run by the Ministry of Intelligence, have complained of solitary confinement, interrogation and torture. Five years ago Zahra Kazemi, a Canadian photographer, died after being beaten there.

Momeni’s family and friends have launched a campaign for her release. “She occupies two worlds, and she was trying to make them understand each other,” said Harry Hellenbrand, the provost of her university. “Maybe that was naïve, but many times the world advances and gets better because of people like her.”

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