Up to a million people have been torn from their homes and forced to live in “re-education” camps in China because of their religion – with children said to be “locked up like farm animals”.
Former inmates have spoken in horrifying detail about the treatment they have endured after being rounded up and imprisoned in western China.
Those arrested are from the Uighur community, a largely Muslim ethnic minority in the Xinjiang region, which borders Afghanistan and Mongolia.
According to the Uighurs, staggering numbers of their own have been taken from their homes in the last two years, with the brutal crackdown going largely unnoticed and unchallenged.
In August this year, a UN human rights committee made a bombshell claim – that up to million people could be being held in those buildings.
Chillingly, the committee said China had “turned the Uighur autonomous region into something that resembles a massive internment camp” under the guise of “combating religious extremism”.
Their words echo those of an earlier US congressional committee on China, which warned that the round ups of Uighurs is “the largest mass incarceration of a minority population in the world today.”
As more details emerged, as well as rare statements from survivors, the world has in recent weeks started to notice the plight of the Uighurs with a growing sense of alarm and horror.
In some towns in the Xinjiang region, many Uighur towns and villages have been left virtually empty after huge numbers were taken away to the camps, according to witnesses.
Speaking anonymously, one official told a newspaper that nearly half of an entire village had been detained, with “only children and old people remaining”.
Others claim they have not heard of anyone leaving the camps in the two years since Chinese police started rounding up members of the Muslim minority.
Perhaps even more disturbing, the detentions are leaving countless children without their mother or father, with the government sending them to overcrowded orphanages thousands of miles away from their homes, according to reports.
One orphanage worker in Xinjiang told Radio Free Asia last year that conditions in the state orphanages are “terrible”.
“Because there are so many children, they are locked up like farm animals in a shed,” he said.
According to human rights groups, the most arbitrary of reasons are used to send people to the reeducation camps, from having an Arabic reader on their mobile phone, to growing a long beard or having contacted someone abroad via Whatsapp.
Human Rights Watch claim anyone with relatives in 26 so-called “sensitive” countries like Indonesia, Kazakstan and Turkey have all been rounded up.
Being born in the 80s and 90s can mean automatic detention – an official directive branded Uighurs from those decades as “members of an unreliable and untrustworthy generation” and targets them for reeducation because they are “susceptible” to be influenced by extremism.
And those who haven’t yet been targeted are subject to intense surveillance – from facial recognition cameras to QR codes on people’s doors, so officials can check the codes to see who is inside at any point, according to observers.
While China simply claims people in Xinjiang are just receiving “vocational training”, reports from inside the camps paint a very different picture – of ethnic cleansing and a campaign to obliterate the centuries-old Uighur culture and identity.
China has long feared that the Uighurs will try to rise up and establish their homeland in Uighurs, while some recent terrorist attacks involving a Muslim Uighur has helped justify the crackdown against extremism in the region.
Rare statements from former inmates tell of how they were forced to eat pork and drink alcohol, which are forbidden to Muslims, renounce Islam and criticise their Islamic beliefs, and recite Communist Party propaganda songs for hours each day.
In interviews with the BBC’s Newsnight programme, former prisoners who were able to leave for other countries told how they had been tortured in the camps.
One man, Omir, said: “They wouldn’t let me sleep, they would hang me up for hours and would beat me.
“They had thick wooden and rubber batons, whips made from twisted wire, needles to pierce the skin, pliers for pulling out the nails.
“All these tools were displayed on the table in front of me, ready to use at any time. And I could hear other people screaming as well.”
And another told how the tactics leave inmates brainwashed: “It was dinner time. There were at least 1,200 people holding empty plastic bowls in their hands – they had to sing pro-Chinese songs to get fed. They were like robots.
“They seemed to have lost their souls. I knew many of them well – we used to sit and eat together, but now they behaved like they were not aware of what they were doing, like someone who had lost their memory after a car crash.”
A Communist Party audio recording transmitted last year to Uighurs via social media platform WeChat referred to the camps as “hospitals” where people who had been “infected by an ideological illness” could be treated.
It said: “They have been infected with religious extremism and violent terrorist ideology, and therefore they must seek treatment from a hospital as an inpatient
“If we do not eradicate religious extremism at its roots, the violent terrorist incidents will grow and spread all over like an incurable malignant tumor.”
In public, though, China has tried to show the centres in a very different light. Last month, the top official in Xinjiang said “vocational education” centres had been set up and were proving effective in staving off terrorism.
Shohrat Zakir said classes were given on Chinese history, language and culture, adding that people in the centres were provided with “nutritious, free diets”.
Few have been convinced by China’s explanations, which have not halted the growing international alarm at their treatment of the Uighurs.
So far, however, no country has dared move from issuing critical statements to putting pressure on China by threatening punitive action such as sanctions.
PM Theresa May only said the UK was “concerned” about the issue back in February during a visit to Beijing, while Donald Trump has ignored a congressional committee report urging place sanctions on officials and companies involved in the “ongoing human rights crisis.”
Meanwhile, China’s brutal campaign against the Uighur continues unabated.