For the handful of elderly men inside one of China's largest mosques, the first bow comes not when prayers begin but as they duck through metal detectors.

Lined with facial recognition security cameras both inside and out, Id Kah mosque in Kashgar is under the constant watch of patrolling police officers armed with batons and riot shields.

Ramadan is a quiet, fearful affair in this oasis town on ancient trade routes. Despite mounting international pressure and condemnation, the massive crackdown on the Uighur people and their shrinking culture here shows no signs of abating for the Muslim holy month.

Widespread intimidation - from inside mosques to family homes - mean residents don't dare utter the traditional Islamic greeting, “as-salaam alaikum”, while fasting is also banned, with restaurants forced to stay open.

At schools and local authority offices, “the Chinese government provides water, food – lunch – to force you to drink and eat,” said Dolkun Isa, president of the World Uyghur Congress, an advocacy group.

Local officials are increasing checks to people’s homes, too, to make sure they aren’t secretly observing the practice, according to a government notice posted online.