Rebel fighters affiliated with the U.S.-backed Syrian Democratic Forces (SDF) have reportedly discovered a “hidden” detention center in northern Syria where Islamic State (ISIS/ISIL) jihadists used the “worst, most violent torture tools” on female prisoners.

The prison was found in the northern Syrian city of Manbij, which was recently liberated from ISIS by the Kurdish People’s Protection Units (YPG)-led SDF. Fighters from the Manbij Military Council, which is part of the SDF, made the discovery.

Citing the independent news agency Arab24, Sky News reports that the prison contained 10 small rooms.

https://www.youtube.com/watch?v=vh7K1RIz2k8

“We discovered an Islamic State group prison for women, with rooms for groups as well as solitary prisoners,” Ibrahim Al-Mohammed from the military council told Arab24. “We found the worst, most violent torture tools, and may God curse them.”

“We found various kinds of pills, including sexual stimulation, contraceptives and narcotic pills which were used by the Islamic State group for torture,” added Omar Mazerli, leader of the military council. “They have very strange ways. This place was very hard to find and it is well hidden, but we got here with God’s will and the efforts of the Military Council.”

The detention center was used to imprison women who defied orders from the Islamic State, also known as IS, points out Arab24.

Video footage purportedly shows writing on the facility’s wall in Arabic that reportedly says, “God, I have wronged myself, and no one forgives sins but you. Forgive me, you are forgiving and merciful.”

In January, ARA News reported that a 21-year-old Syrian girl had been tortured to death in Manbij by a female ISIS jihadist for violating the Islamic dress code imposed by the terrorist group.

The news outlet did not identify the prison where the girl was held, saying only that it was an “ISIS detention center in the Syrian border city of Manbij.” It may have been the recently discovered facility.

“She was harshly tortured. We have received her dead body full of physical effects of torture,” a family member of the victim told ARA News on condition of anonymity. “We cannot even protest against this horrible crime. The only judicial department in Manbij is the Sharia Court, which supports such crimes.”

“The militants practice all kinds of violence against the female prisoners. Once you protest, they will beat you to death,” an unnamed informed local source quoted a former female prisoner in Manbij as saying.

ISIS formed the al-Khansaa brigade, an all-women police or religious enforcement unit, to patrol its de facto Syrian capital of Raqqa because men are prohibited from touching females under Sharia law.

Although it remains unclear if the terrorist group established similar groups in other territories, the Soufan Group, a terrorism research firm, predicted in February that “as with male recruits, female recruits may begin to be directed toward other Islamic State territories.”

News of the Manbij women’s prison discovery comes just weeks after the SDF recaptured Manbij from ISIS, liberating thousands of captive civilians after months of fighting.