BEIJING >> The U.N. accused China of serious human rights violations that may amount to “crimes against humanity” in a long-delayed report examining a crackdown on Uyghurs and other mostly Muslim ethnic groups. Beijing on Thursday denounced the assessment as a fabrication cooked up by Western nations.

Human rights groups have accused China of sweeping a million or more people from the minority groups into detention camps where many have said they were tortured, sexually assaulted, and forced to abandon their language and religion. The camps were just one part of what the rights organizations have called a ruthless campaign against extremism in the far western province of Xinjiang that also included draconian birth control policies and all-encompassing restrictions on people’s movement.

The assessment from the Geneva-based U.N. human rights office was released in the final minutes of High Commissioner for Human Rights Michelle Bachelet’s four-year term. It largely corroborated earlier reporting by researchers, advocacy groups and the news media, and it added the weight of the world body to the conclusions. But it was not clear what impact it would have.

Still, among Uyghurs who have fled overseas, there was a palpable sense of relief that the report had finally seen the light of day since many worried that it would never be published. Several saw it as a vindication of their cause and of years of advocacy work.

“The report is pretty damning, and a strong indictment on China’s crimes against humanity,” said Rayhan Asat, a Uyghur lawyer whose brother is imprisoned in Xinjiang. “It’s a really long-awaited recognition of the Uyghurs and their unimaginable suffering, coming from the world’s most authoritative voice on human rights.”

Human rights groups, the U.S., Japan and European governments also welcomed the report. It had become caught up in a tug-of-war between China and major Western nations as well as human rights groups that have criticized the repeated delays in releasing the document. Many Geneva diplomats believe it was nearly complete a year ago.

The assessment released late Wednesday concluded that China has committed serious human rights violations under its anti-terrorism and anti-extremism policies and calls for “urgent attention” from the U.N., the world community and China itself to address them.

Human rights groups renewed calls for the U.N. Human Rights Council, which meets next month, to set up an independent international body to investigate the allegations. But China showed no sign of backing off its blanket denials or portraying the criticism as a politicized smear campaign.

“The assessment is a patchwork of false information that serves as political tools for the U.S. and other Western countries to strategically use Xinjiang to contain China,” Foreign Ministry spokesperson Wang Wenbin said. “It again shows that the U.N. Human Rights Office has been reduced to an enforcer and accomplice of the U.S. and other Western countries.”

In a sign of China’s fury, it issued a 122-page rebuttal, entitled “Fight against Terrorism and Extremism in Xinjiang: Truth and Facts,” that was posted by the U.N. along with the report.

The U.N. findings were drawn in part from interviews with more than two dozen former detainees and others familiar with conditions at eight detention centers. They described being beaten with batons, interrogated while water was poured on their faces and forced to sit motionless on smalls stools for long periods.

Some said they were prevented from praying — and were made to take shifts through the night to ensure their fellow detainees were not praying or breaking other rules. Women told of being forced to perform oral sex on guards or undergo gynecological exams in front of large groups of people.

The report said that descriptions of the detentions were marked by patterns of torture and other cruel and inhumane treatment and that allegations of rape and other sexual violence appeared “credible.”

“The extent of arbitrary and discriminatory detention of members of Uyghur and other predominantly Muslim groups … in (the) context of restrictions and deprivation more generally of fundamental rights … may constitute international crimes, in particular crimes against humanity,” the report said.

It made no mention of genocide, which some countries, including the United States, have accused China of committing in Xinjiang.

U.S. Secretary of State Antony Blinken welcomed the report, saying in a statement that it “deepens and reaffirms our grave concern.” He added: “We will continue to work closely with our partners, civil society, and the international community to seek justice and accountability for the many victims.”

The rights office said it could not confirm estimates that a million or more people were detained in the internment camps in Xinjiang, but added it was “reasonable to conclude that a pattern of large-scale arbitrary detention occurred” at least between 2017 and 2019.

U.N. Secretary-General Antonio Guterres believes the assessment “clearly identifies serious human rights violations in the Xinjiang region,” U.N. spokesman Stephane Dujarric said Thursday. He said the U.N. chief “very much hopes” China will follow recommendations in the assessment.

Beijing has closed many of the camps, which it called vocational training and education centers, but hundreds of thousands of people continue to languish in prison, many on vague, secret charges.

The report called on China to release all individuals arbitrarily detained and to clarify the whereabouts of those who have disappeared and whose families are seeking information about them.

“Japan is highly concerned about human rights conditions in Xinjiang, and we believe that it is important that universal values such as freedom, basic human rights and rule of law are also guaranteed in China,” Chief Cabinet Secretary Hirokazu Matsuno said.

Germany and Britain also welcomed its publication.

British Foreign Secretary Liz Truss, who is also the frontrunner in the contest to replace Boris Johnson as prime minister, noted that the report “includes harrowing evidence, including first-hand accounts from victims, that shames China in the eyes of the international community.”

Human Rights Watch said the report laid a solid foundation for further U.N. action to establish accountability for the abuses.

“Never has it been so important for the U.N. system to stand up to Beijing, and to stand with victims,” said John Fisher, the deputy director of global advocacy for the group.

Rahima Mahmut, U.K. director of the World Uyghur Congress, said she was relieved the report is finally out — but had no hope it would change the Chinese government’s behavior and called on the international community to send a signal to Beijing that “business cannot be as usual.”

That the report was released was in some ways as important as its contents.

Outgoing rights chief Bachelet said she had to resist pressure both to publish and not publish. She had announced in June that the report would be released by end of her four-year term on Aug. 31, triggering a swell in back-channel campaigns — including letters from civil society, civilians and governments on both sides of the issue.

Why she waited until the last minute to release the report remains unclear.

Critics had said a failure to publish the report would have been a glaring black mark on her tenure.

“The inexcusable delay in releasing this report casts a stain” on the record of the U.N. human rights office, said Agnès Callamard, the secretary-general of Amnesty International, “but this should not deflect from its significance.”