BEIJING (AP) — When a Chinese government mass detention campaign engulfed Memtimin Emer’s native Xinjiang region three years ago, the elderly Uighur imam was swept up and locked away, along with three of his sons.

Now, a leaked database exposes in extraordinary detail the main reasons for the detentions of Emer, his three sons, and hundreds of others in their neighborhood: Their religion and their family ties.

The database profiles the internment of 311 individuals with relatives abroad in Karakax County, and lists information on more than 2,000 of their relatives, neighbors and friends. Each entry includes the detainee’s name, address, national identity number, detention date and location, along with a dossier on their family, religious and community background, the reason for detention, and a decision on whether to release them.

Taken as a whole, the database offers the fullest view yet into how Chinese officials decided who to put into and let out of detention camps, as part of a crackdown that has locked away more than a million ethnic minorities, most of them Muslims.

The database shows that the state focused on religion as a reason for detention — not just political extremism, as authorities claim, but ordinary activities such as praying or attending a mosque. It shows that people with detained relatives are themselves more likely to end up in a camp, criminalizing entire families like Emer’s in the process.

“It’s very clear that religious practice is being targeted,” said Darren Byler, a University of Colorado researcher studying Xinjiang. “They want to fragment society, to pull the families apart and make them much more vulnerable to retraining and reeducation.”

The Xinjiang regional government did not respond to faxes requesting comment. Asked whether Xinjiang is targeting religious people and their families, foreign ministry spokesman Geng Shuang said “this kind of nonsense is not worth commenting on.”

The Chinese government has said in the past that the detention centers are for voluntary job training, and that it does not discriminate based on religion.

China has struggled for decades to control Xinjiang, where the native, predominantly Muslim Uighurs have long resented Beijing’s rule. After militants set off bombs at a train station in Xinjiang’s capital in 2014, President Xi Jinping launched a so-called “People’s War on Terror”, turning Xinjiang into a digital police state.

The leak of the database follows the release in November of a classified blueprint. Obtained by the International Consortium of Investigative Journalists, which includes the AP, the blueprint shows the camps are in fact forced ideological and behavioral re-education centers run in secret.

The database comes from sources in the Uighur exile community, and does not spell out which government department issued it or for whom. The detainees listed come from Karakax County, a traditional settlement on the edge of Xinjiang’s Taklamakan desert where more than 97 percent of its roughly 650,000 residents are Uighur. The list was corroborated through interviews with former Karakax residents, identity verification tools, and other lists and documents.

The database shows that cadres compile dossiers on detainees called the “three circles”, encompassing their relatives, community, and religious background.

The detainees and their families are then classified by rigid categories. Households are designated as “trustworthy” or “not trustworthy”. Families have “light” or “heavy” religious atmospheres, and the database keeps count of how many relatives of each detainee are locked in prison or sent to a “training center”.

Officials used these categories to determine how suspicious a person was – even if they hadn’t committed any crimes.

Reasons listed for internment include “minor religious infection,” “disturbs other persons by visiting them without reasons,” “relatives abroad,” or “thinking is hard to grasp.”

Former student Abdullah Muhammad described Emer as one of the most respected imams in the region. He fed the hungry, bought coal for the poor, and treated the sick with free medicine.

But though Emer gave Party-approved sermons, he refused to preach Communist propaganda, Muhammad said, eventually running into trouble with authorities. He was stripped of his position as an imam in 1997.

Though he stopped attending religious gatherings, in 2017 authorities detained Emer, now in his eighties, and sentenced him to prison. The database cites four charges in various entries: “stirring up terrorism”, acting as an unauthorized “wild” imam, following the strict Saudi Wahhabi sect and conducting illegal religious teachings.

Muhammad called the charges false. Emer stopped his preaching, practiced a moderate sect of Islam and never dreamed of hurting others, let alone stirring up “terrorism,” Muhammad said.

Emer’s three sons, too, were all thrown in camps for religious reasons, though they weren’t charged with crimes. It shows their relation to Emer and their religious background caused officials to believe they were too dangerous to let out.

“His family’s religious atmosphere is thick. We recommend he (Emer) continue training,” notes an entry for his youngest son, Emer Memtimin.

But it wasn’t just the religious who were detained. Pharmacist Tohti Himit was detained in a camp for having gone multiple times to one of 26 “key”, mostly Muslim countries, the database said. A former employee said Himit was secular, keeping his face well-shaved.

“He wasn’t very pious, he didn’t go to the mosque,” said Habibullah, who declined to give his first name out of fear of retribution against family still in China. “I was shocked by how absurd the reasons for detention were.”

The database says Himit had gone to a mosque three times in 2008, once to attend his grandfather’s funeral. In 2014 he had gone to another province to get a passport and go abroad.

That, the government concluded, showed Himit was “dangerous” and needed to “continue training.”

Emer is now under house arrest due to health issues, Muhammad has heard. It’s unclear where Emer’s sons are. Though deprived of his mosque and his right to teach, Emer had quietly defied the authorities for two decades by staying true to his faith.

“He never bowed down to them — and that’s why they wanted to eliminate him,” Muhammad said.