China has denied allegations from a UN committee that it is detaining millions of Muslim Uighur citizens in the western province of Xinjiang, as pressure mounted to acknowledge what the Geneva-based group called “many credible reports” of the existence of internment centres.

A UN panel on racial discrimination said on Friday that it was “deeply concerned” by reports that China “has turned the [Xinjiang] Uyghur autonomous region into something that resembles a massive internment camp that is shrouded in secrecy”.

“There are estimates that upwards of 1m people are being held in so-called counter-extremism centres and another 2m have been forced into so-called re-education camps for political and cultural indoctrination,” said Gay McDougall, vice-chairwoman of the UN Committee on the Elimination of Racial Discrimination.