TUNIS — She was just 21 when she was arrested by Tunisia’s state police, who hauled her into an Interior Ministry office and “beat me up so hard that I don’t even remember how I found myself there.” But that was not the worst part.

Hamida Ajengui said she was stripped, and hung upside down by a dozen police officers who hurled abuse at her and threatened her with rape.

“I was a girl,” Ms. Ajengui, now 46, said in an interview. “I was raised in a certain environment where it is ethical to be a moral, respectable, polite person. Then all of a sudden I was taken to this place where they strip you — they took all my clothes off — they leave you completely naked.”

Tunisia has embarked on a bold and painful experiment, gathering testimony from victims of six decades of abuses under two dictatorships before its revolution four years ago led to a still-fledgling democracy. Already, thousands have arrived to lodge complaints at the country’s Truth and Dignity Commission, which is scheduled to begin public hearings in June with the goal of exposing the violations, making reparations and holding the abusers accountable in a search for national reconciliation.

Just a few months into the process, 12,000 victims have come forward, most of them men. But what has surprised even longtime human rights activists is the number of women starting to tell stories of extreme cruelty, sexual violence and rape.

By far the most difficult and traumatic cases, commission workers say, are accounts like Ms. Ajengui’s, because women are seen to embody family honor in this conservative society.

Women were tortured as brutally as men were. But they suffered an added stigma — that of rape and sexual assault. Such abuse was used as a systematic and institutionalized form of torture, often directed at women for no reason other than that they were married or related to a member of the opposition.

Others were themselves activists — leftists, nationalists, unionists, Islamists or students — who were arrested alongside their male colleagues. Ms. Ajengui’s offense was that she was raising money to help support prisoners’ families.

Prisoners, men and women, found themselves not only ostracized, but also blocked from jobs and education, and made to sign in at a police station two or three times a day. “It was like a punishment to your whole life,” Ms. Ajengui said.