China¡¯s ¡°arbitrary and discriminatory detention¡± of members of Uyghur and other predominantly Muslim groups in the country¡¯s northwestern Xinjiang region ¡°may constitute international crimes, in particular crimes against humanity,¡± the U.N. Human Rights Office said in a damning report released Wednesday.

¡°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,¡± said the much-anticipated report by outgoing U.N. High Commissioner for Human Rights Michelle Bachelet.

The report was hailed by human rights groups for adding credibility to long-running concerns over violations that some Western nations have labeled genocide. Japan¡¯s top spokesman also expressed ¡°grave concern¡± over the findings.