Human Rights Watch says it has confirmed that police in Russia's Chechnya region rounded up, tortured, and humiliated dozens of gay or bisexual men during the spring of 2017 in "an apparent effort to purge them from Chechen society."

In a 29-page report released on May 26, the U.S.-based nongovernmental rights group said the "antigay purge" lasted from late February until at least early April -- and that "it was ordered and conducted by officials in Chechnya."

The report says the speaker of Chechnya’s parliament, Magomed Daudov, "seems to have played a key role in both securing and giving approval from the Chechen leadership to set in motion the purge."

It says most of the purge victims interviewed by Human Rights Watch "reported hearing the police who held and abused them refer to Daudov and to orders he allegedly issued about violence against gay men."

It also said three of the interviewed victims witnessed Daudov’s presence at unofficial detention facilities in Grozny and Argun, where the abuses were carried out.

Human Rights Watch said the purge began in Argun, about 18 kilometers east of Grozny, during the last week of February.

It says police who detained a young gay man found "intimate photographs and messages" on his mobile phone indicating he was homosexual.

"Using the information from the man's phone together with information the man provided under torture, the officials established the identity of several of his gay contacts," Human Rights Watch reported.

"The police officials reported their findings to their superior, who apparently raised it with Magomed Daudov," it said.

It said the first victim's contacts also were "abducted and tortured" by police, who forced them to provide information about other people presumed to be gay.

"It was like a chain," one of the former detainees told Human Rights Watch. "They get one person, go through his phone, torture him, make him name some others, get those others, and so it goes."

"In the place where I was held, we were four [gay men] at first, but several days later we were already 20," he said.

Graeme Reid, director of the lesbian, gay, bisexual, and transgender rights program at Human Rights Watch, said most of the victims were held and tortured for several days or even weeks.

Several allegedly died and some are still thought to be in detention.

Reid also said that when police returned most of the men to their families, they exposed their sexual orientation and indirectly encouraged their relatives to carry out "honor killings."

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Reid also said victims who have fled Chechnya after their ordeal remain in danger elsewhere in Russia, with threats continuing against them.

"All of the victims suffered repeated beatings," the report said. "Security officials kicked them with booted feet, beat them with polypropylene pipes and sticks, and made other inmates beat them" -- mostly on the men’s buttocks and legs.

"They put you face down on the floor and beat you with pipes," one victim told Human Rights Watch. "Then they force other prisoners [held for allegedly supporting insurgents or for alleged drug offenses] to carry on with the beating. Each man gets some 70 to 80 blows. And so it goes.... And you literally turn black and blue from waist to toes."

The rights group says local Chechen authorities also used electrocution devices to torture the victims.

Former detainees described those devices as machines with a knob on one side and wires sticking out of it with metal clips at the ends -- clips which were attached to the victims' fingers, toes, and earlobes.

"They turn the knob, electric current hits you, and you start shaking," a former detainee told Human Rights Watch. "And they keep turning the hellish machine, and the pain is just insane. You scream and scream and you no longer know who you are."

"Finally, you faint," the former detainee continued. "It all goes dark. But when you come to your senses, they start all over again. And once they’re done with you and you get your bearings, you hear other inmates screaming. The sounds of torture are just there all day, and at some point you start losing your mind."

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Since Russia's Novaya Gazeta newspaper first reported the abuses in early April, gay men from Chechnya have given personal accounts to RFE/RL and other media about their ordeal in the North Caucasus region, which Chechnya's leader, Ramzan Kadyrov, has ruled for the past decade through what critics say is brutal repression -- and with strong Kremlin support.

"Law enforcement and security agencies under Kadyrov's de facto control have abducted people from homes, work places, and the streets, held them in secret locations, and carried out enforced disappearances, torture, extrajudicial executions, and collective punishment practices," Human Rights Watch said.

Yulia Gorbunova, a Moscow-based researcher for Human Rights Watch, noted that Russia's federal authorities initially dismissed the abuse allegations in Novaya Gazeta, which included reports of Daudov’s repeated visits to the unofficial detention facility in Argun.

But under growing international pressure,President Vladimir Putin said on May 5 that he would speak to top law enforcement officials about the allegations -- though he also suggested that the reports might be merely "rumors"-- and federal agencies have reportedly begun inquiries.

"Chechnya’s leadership said it was ready to cooperate with federal inquiries, but also vehemently denied the very existence of gay people in Chechnya and they repeatedly berated and threatened journalists and human rights defenders for raising the issue," Gorbunova told RFE/RL.

Meanwhile, Russian federal officials "have repeatedly pointed to the lack of victim complaints to suggest the allegations are merely rumors," Gorbunova said.

"The men who survived Chechnya's gay-purge ordeal are caught between two fires: their well-grounded fears of official retaliation, and fear of violence from their own families," Reid said. "Russian officials need to address the victims' extreme vulnerability and their legitimate fears about coming forward to complain."

Human Rights Watch concludes that the federal investigations should be "thorough and capable of bringing the perpetrators to account."

It says authorities should take extra steps to protect victims, witnesses, and their immediate families.

The rights group also called on foreign government to maintain pressure on Moscow, including regular inquiries about the progress of the investigation.

It said the European Union, the United States, and other democratic countries also should "provide prompt, safe sanctuary to victims of the purge seeking refuge in safe countries."