Uighur people pick up their children from school in Kashgar City in Xinjiang, China, in July 2017. (Anadolu Agency/Getty Images)

THE TRUMP administration was rightly excoriated and forced to retreat when it adopted the tactic of separating the children of undocumented immigrants from their detained parents earlier this year. Yet this cruel and since-rescinded practice pales beside China’s ongoing mistreatment of children in its western Xinjiang province. There, thousands of minors from the Uighur and Kazakh ethnic minorities have been involuntarily separated from their families and sent to orphanages and boarding schools, where they are being taught to abandon their native languages and Muslim faith for Mandarin Chinese and the Communist Party.

Facts are hard to come by when it comes to Beijing’s ongoing campaign of repression in Xinjiang, an area more than four times the size of Germany with a population of about 23 million, of whom about half are Uighurs or other Muslims. But 1 million people are believed to have been detained in political reeducation camps, while many others have been forced into exile in what human rights groups call the biggest mass violation of human rights in China since the Cultural Revolution.

In a report published last week, the Associated Press pieced together a picture of what has happened to the children of those victims, based on interviews with 15 Muslims and a review of procurement documents. Though fragmentary, the details are stunning. The AP said there was “evidence that the government is placing the children of detainees and exiles into dozens of orphanages across Xinjiang.” It cited documents indicating the government has budgeted $30 million to build or expand 45 orphanages this year, with enough beds to house about 5,000 children.

The government has also built a network of boarding schools, and the AP report quoted parents as saying that all Uighur children in some districts were required to attend them. Like the orphanages, the schools are typically surrounded by fences and patrolled by guards. One Uighur told the AP that “her neighbors too were only allowed to visit their kids at boarding school on Wednesday nights, and even then they had to hand them candies through a fence.”

Inside the facilities, children as young as 5 are drilled in Mandarin and Communist Party slogans, much like their parents in the reeducation camps. They are penalized for speaking Uighur or other minority languages. Scholars compared the indoctrination to that to which the United States, Canada and Australia once subjected indigenous children, with grievous results for the children and their communities. Uighur intellectuals say the regime of Xi Jinping is aiming to extinguish their language, culture and Muslim identity.

The Trump administration was forced to end its separations of migrant families by lawsuits and intense publicity. But there is no rule of law in Xinjiang, and the regime has done its best to stifle reporting on its repression. It still denies the mass detentions, despite reports by numerous independent groups and hearings in Congress and the United Nations. More must be done to call attention to these extraordinary violations of human rights; perhaps Mr. Xi, like President Trump, can be shamed into changing course.