China targets Uighur Muslim imams in Xinjiang crackdown
The imams were targeted due to their role as religious leaders, preaching and organising group prayers, according to testimonies cited in a report compiled by the Uyghur Human Rights Project
Detainees have been charged with "propagating extremism", "gathering a crowd to disturb social order", and "inciting separatism".
The UHRP report cited 1,046 clerics who have been detained since 2014 with at least 304 sent to prison instead of "re-education camps", which rights group describe as concentration camps.
The court documents cited in the report show that 96 percent of those sentenced were handed at least five years in prison, 26 percent given 20 years or more, and 14 were handed life sentences.
Over the past four years, Chinese authorities have carried out a brutal campaign of forced assimilation targeting Uighurs, an ethnic Turkic minority native to Xinjiang.
Rights groups and former inmates see the measures as part of a campaign to forcefully assimilate Uighurs and other minorities into the country's majority ethnic Han society, diluting their unique cultures and religious beliefs.
Muslims in Xinjiang are barred from fasting during the holy month of Ramadan and have allegedly been forced to drink alcohol and eat pork - both forbidden in Islam - in internment camps.
China has strongly denied the allegations, saying training programmes, work schemes and better education have helped stamp out extremism in the northwestern region and raise income.
The crackdown has triggered sanctions from the West, and on Wednesday a group of Western countries are slated to hold a UN event on China's repression of the Uighurs.