UN's human rights experts have expressed alarm at the reports of mass detention of Uighurs in China and called for the release of those held on counter terrorism "pretext".
There were reports that about one million Muslim Uighurs in western Xinjiang region were held in re-education camps.
The UN Committee on the Elimination of Racial Discrimination cited estimates that “from tens of thousands to upwards of a million Uighurs” may be detained in the far western Xinjiang province.
Beijing has denied the allegations but admitted that some religious extremists were being held for re-education.
China blames Islamist militants and separatists for unrest in the region.
A review earlier this month by the UN committee said reports suggested that Beijng had "turned the Uighur autonomous region into something that resembles a massive internment camp".
China responded that Uighurs enjoyed full rights but Beijing made a rare admission that "those deceived by religious extremism... shall be assisted by resettlement and re-education".
Beijing denies detaining one million Uighurs
Xinjiang has seen intermittent violence - followed by crackdowns - for years.