Women in China's system of detention camps for ethnic Uighurs and other Muslims in its western region of Xinjiang were subject to rape, sexual abuse and torture, according to a BBC report on Wednesday.
The British broadcaster said on its website "several former detainees and a guard have told the BBC they experienced or saw evidence of an organised system of mass rape, sexual abuse and torture."
The allegations could not be independently verified by Reuters.
Beijing strongly denies accusations of abuse in Xinjiang, and has said the complexes it set up in the region provided vocational training to help stamp out Islamist extremism and separatism, and to teach new skills. Those in the facilities had since "graduated", it says.
Asked on Wednesday about the BBC report, foreign ministry spokesman Wang Wenbin said it "is wholly without factual basis" and the people interviewed by the BBC have been "proved multiple times" to be "actors disseminating false information."
The United States accuses China of committing genocide against Uighurs in Xinjiang.
Last year, a report by German researcher Adrian Zenz published by the Washington-based Jamestown Foundation think tank accused China of using forced sterilisation, forced abortion and coercive family planning against minority Muslims. China said the allegations were groundless and false.