Turkey has condemned China's treatment of its Turkic Muslim Uyghur minority population as "a great cause of shame for humanity."
"It is no longer a secret that more than 1 million [Uyghurs] incurring arbitrary arrests are subjected to torture and political brainwashing in internment camps and prisons," Turkish Foreign Ministry spokesman Hami Aksoy said in a statement late on February 9.
Aksoy also said that Turkey had learned of the "tragic" death in custody of Uyghur poet and musician Abdurehim Heyit, who had been sentenced to eight years over one of his songs.
China's Embassy in Ankara called Aksoy's comments "completely unacceptable."
Beijing faces growing international pressure over its policies toward Uyghurs and members of other Muslim Turkic language-speaking communities in the northwestern region of Xinjiang.
A report by a UN panel of experts last year said that an estimated 1 million of them were being held in "counterextremism centers."
They said millions more had been forced into reeducation camps.
China says that the facilities are "vocational education centers" aimed at helping people steer clear of terrorism and allow them to be reintegrated into society.
The Uyghurs -- of whom there are some 15 million in China -- have long complained about their treatment under Beijing's rule.
In a show of support, a bipartisan group of U.S. senators in late January nominated Ilham Tohti, a jailed Chinese academic of Uyghur origin, for the Nobel Peace Prize.
"This nomination could not be more timely, as the Chinese government and Communist Party continue to perpetrate gross human rights violations with over a million Uyghurs and other ethnic minority Muslims detained in 'political reeducation' camps," Republican Senator Marco Rubio said on January 30.