More than 100 British lawmakers signed a letter to the Chinese ambassador Wednesday condemning what they described as “a systematic and calculated programme of ethnic cleansing against the Uighur people” in China’s far western Xinjiang region.

“When the world is presented with such overwhelming evidence of gross human rights abuses, nobody can turn a blind eye,” said the cross-party letter, which was signed by 130 lawmakers.

The letter referred to reports of forced population control, including coerced sterilisations and abortions, mass detention of Uighur Muslims in Xinjiang, as well as video apparently showing a large number of blindfolded and shaven men waiting to be loaded onto trains. The lawmakers said the video bore “chilling” similarities to footage of Nazi concentration camps.