A report from the Paris-based Kurdistan Human Rights Network (KHRN) on Sunday charged Iranian officials with killing one person who was detained during last month’s protests and torturing several others.

Three imprisoned students told KHRN they were threatened with rape and ordered not to discuss sexual and physical violence they experienced or witnessed.

KHRN said it has accumulated “evidence and testimony from people that showed high level of violence was perpetrated by security forces on those detained during the protests.”

Kurdish news service Rudaw noted in its English-language report on KHRN’s findings that Iran’s Kurdish areas are “some of its poorest, making its residents among the hardest hit by the price hike” in gasoline that triggered the protests. Iranian Kurds also “experienced some of the worst of the crackdown.”

The number of people killed and imprisoned during the Iranian regime’s crackdown on protests remains in dispute. As KHRN observed, obtaining solid information is difficult not only because the authoritarian government (really two separate governments, one secular and one religious, both authoritarian) is highly secretive, but because numerous police and security agencies conducted the crackdown. The regime is currently conducting a violent crackdown on citizens who gather to remember the dead from November, in part because it does not wish attention drawn to how many citizens it killed last month.

Some of the worst abuses reportedly occurred in facilities run by Iran’s Islamic Revolutionary Guard Corps (IRGC), which has been designated a foreign terrorist organization by the U.S. government. According to KHRN, the IRGC is threatening the families of detainees who were tortured and sexually abused into silence.

“After we were detained, they placed black bags over our head and forced us into a Peugeot 405, then took us to an unknown location. They kept us in rooms half a meter by half a meter wide. We could hear the screams of the other detainees being tortured at night, and the rooms were so small that we couldn’t stretch our legs,” one former detainee told KHRN.

“They kept us hungry for a long time – they did not even give us a piece of bread. At night, they would take us to the yard of the detention center and force us to take off our clothes. They would use a pipe to pour cold water on us, then they would start beating us,” he said.

Another detainee said teenagers were held at the same detention center and were tortured until they lost consciousness. “We did not know where they take these teenagers after they fell unconscious and we don’t know if they are still alive or dead,” he said.

Amnesty International issued a statement on Saturday expressing concern that thousands of detainees in Iran — including political activists, journalists, and students — are at risk of physical and sexual abuse.

“Children as young as 15 have been arrested and detained alongside adults in prisons notorious for torture. Detainees have been subjected to torture and other ill-treatment; they have been beaten, punched, kicked and flogged by security forces. Many are being denied access to their families and lawyers,” Amnesty said.

Amnesty International is circulating a petition calling on the head of Iran’s judiciary to “protect detainees from torture and other ill-treatment, immediately and unconditionally release all those detained arbitrarily, and ensure that UN experts are given immediate access to detention centers and prisons and to families of those killed and arrested in order to conduct fact-finding investigations.”

Independent human rights experts working under the auspices of the United Nations said last week that they were “shocked at reports of the ill-treatment of those detained during the protests.”

“Reports suggest that detainees are being tortured or are suffering other forms of ill-treatment, sometimes to extract forced confessions. Some are also reportedly being denied medical treatment, including for injuries caused by the security forces’ use of excessive force,” the U.N. experts said.

The opposition People’s Mojahedin Organization of Iran (MEK) published the names of 14 more “martyrs” killed during the November protest, for a total of 615 victims identified by the organization.

MEK agrees with the high-end estimate published by the Reuters news service that at least 1,500 protesters were killed, 4,000 injured, and over 12,000 detained.