ALMATY, Kazakhstan -- Three men have staged separate pickets outside the Chinese Consulate in Kazakhstan's largest city, Almaty, demanding the release of their relatives and other ethnic Kazakhs being held in custody in China's northwestern Xinjiang region.

Marat Qurbanov, Serik Azhibai, and Baibolat Kunbolatuly said on January 22 that their relatives and three other ethnic Kazakhs, some of whom are Kazakh passport-holders, were being held in "political prisons."

They called for detailed information about their whereabouts and their release.

Nobody from the consulate met with the demonstrators. Security officers asked them to submit their requests in writing.

Similar protests have taken place in Kazakhstan in recent months, with demonstrators demanding that the Kazakh authorities officially intervene in the situation faced by ethnic Kazakhs in Xinjiang.

In August 2018, the United Nations said an estimated 1 million Uyghurs and members of other indigenous ethnic groups in the region were being held in "counterextremism centers."

The UN said millions more had been forced into so-called “reeducation camps.” China denies that the facilities are internment camps.

People who have fled the province say that thousands of ethnic Kazakhs, Uyghurs, and other Muslims in Xinjiang are undergoing "political indoctrination" at a network of camps.

Kazakhs are the second-largest Turkic-speaking indigenous community in Xinjiang after Uyghurs. The region is also home to ethnic Kyrgyz, Tajiks, and Hui, also known as Dungans. Han, China's largest ethnicity, is the second-largest community in Xinjiang.