GENEVA, Switzerland (AFP) — The United Nations has released a bombshell report into serious human rights abuses in China's Xinjiang region, saying torture allegations were credible and citing possible crimes against humanity.

"The extent of arbitrary and discriminatory detention of members of Uyghur and other predominantly Muslim groups… may constitute international crimes, in particular crimes against humanity," the report released late Wednesday said.

"Serious human rights violations have been committed in XUAR in the context of the government's application of counter-terrorism and counter -'extremism' strategies," the UN report said, referring to the Xinjiang Uyghur Autonomous Region.

It said the world must now pay "urgent attention" to the human rights situation in XUAR.

The report was in the making for around a year and its release by Michelle Bachelet, the UN human rights chief, was bitterly opposed by China.

Bachelet was determined to release it before her four-year term as the UN high commissioner for human rights expired at the end of August — and did so with 13 minutes to spare at 11:47 p.m. in Geneva.

"I said that I would publish it before my mandate ended and I have," Bachelet said in an email sent to AFP on Thursday.

Happy life

China's mission in Geneva hit out at the report and maintained its firm opposition to its release.

"Based on the disinformation and lies fabricated by anti-China forces and out of presumption of guilt, the so-called 'assessment' distorts China's laws and policies, and wantonly smears and slanders China, and interferes in China's internal affairs," it said.

"People of all ethnic groups in Xinjiang are living a happy life in peace and contentment. It is the greatest human rights protection and the best human rights practice," the mission insisted.

China has been accused for years of detaining more than one million Uyghurs and other Muslims in the region.

Beijing has vehemently rejected the claims, insisting it is running vocational centers designed to curb extremism.

The report raised concerns about the treatment of people held in China's so-called "Vocational Education and Training Centers."

"Allegations of patterns of torture or ill-treatment, including forced medical treatment and adverse conditions of detention, are credible, as are allegations of individual incidents of sexual and gender-based violence," the report said.

The UN Human Rights Office could not confirm how many people were affected by the VETC but concluded that the system operated on a "wide scale" across the entire region.

The number in the VETC, at least between 2017 and 2019, "was very significant, comprising a substantial proportion of the Uyghur and other predominantly Muslim minority populations."

Campaigners have accused China of practicing forced sterilization of women.

The report said there were "credible indications of violations of reproductive rights through the coercive enforcement of family planning policies."

The UN Human Rights Council should now investigate China's alleged crimes against humanity "and hold those responsible to account," Human Rights Watch's China director Sophie Richardson said.