Chinese state media have released a video appearing to show a Uighur musician previously reported to have died in a detention camp.
The video, dated 10 February, features a man said to be Abdurehim Heyit stating that he is in “good health”.
Turkey earlier called on China to close the camps following reports of his death. Up to a million Uighurs are reportedly being detained.
Some Uighurs have questioned the video’s authenticity.
Nury Turkel, chairman of the US-based Uyghur Human Rights Project, told the BBC that some aspects of the video were “suspicious”.
The Uighurs are a Muslim Turkic-speaking minority based in the north-western Xinjiang region of China, which has come under intense surveillance by Chinese authorities. Their language is close to Turkish and a significant number of Uighurs have fled to Turkey from China in recent years.
What is in the video?
The video was released by China Radio International’s Turkish-language service, which said Turkey’s criticism of China was unfounded.
In it, Mr Heyit appears to say he is “in the process of being investigated for allegedly violating national laws”.
What did Turkey say?
Its foreign ministry had said that detained Uighurs were being subjected to “torture” in “concentration camps”.
Foreign ministry spokesman Hami Aksoy said the reports of Mr Heyit’s death “further strengthened the Turkish public’s reaction to the serious human rights violations in Xinjiang”.
“The reintroduction of concentration camps in the 21st Century and the systematic assimilation policy of Chinese authorities against the Uighur Turks is a great embarrassment for humanity,” Mr Aksoy said.
He called on UN Secretary General Antonio Guterres “to take effective steps to end the human tragedy” there.
China has described the comments as “completely unacceptable”.