China has imprisoned or detained at least 630 imams and other Muslim religious figures since 2014 in its crackdown in the Xinjiang region, according to new research by a Uyghur rights group.
The research, compiled by the Uyghur Human Rights Project and shared with the BBC, also found evidence that 18 clerics had died in detention or shortly after.
Many of the detained clerics faced broad charges like "propagating extremism", "gathering a crowd to disturb social order", and "inciting separatism".
According to testimony from relatives, the real crimes behind these charges are often things like preaching, convening prayer groups, or simply acting as an imam.
The UHRP, working with rights group Justice for All, tracked the fates of 1046 Muslim clerics - the vast majority of them Uyghurs - using court documents, family testimony and media reports from public and private databases.
While all 1046 clerics were reportedly detained at some point, in many cases corroborating evidence was not available because of China's tight control over information in the region.
Among the 630 cases where it was, at least 304 of the clerics appeared to have been sent to prison, as opposed to the network of "re-education" camps most closely associated with China's mass detention of the Uyghurs.
Where information was available from court documents or testimony about the length of the prison sentence, the punishments reflect the harsh nature of Xinjiang justice: 96 percent sentenced to at least five years and 26 percent to 20 years or more, including 14 life sentences.
The database, which drew on research by the Uyghur activist Abduweli Ayup, as well as the Xinjiang Victims Database and Uyghur Transitional Justice Database, is by no means exhaustive - representing only a fraction of the total estimated number of imams in Xinjiang.
But it shines a light on the specific targeting of religious figures in Xinjiang, appearing to support allegations that China is attempting to break the religious traditions of the Uyghurs and assimilate them into Han Chinese culture.
China is believed to have detained more than a million Uyghurs and other Muslims in Xinjiang, a large region in north-western China that is home to various ethnically Turkic peoples. The state has been accused of human rights abuses in the region, including forced labour, sterilisation and rape.