Three times a day, alarms ring out through the streets of China's ancient Silk Road city of Kashgar, and shopkeepers rush out of their stores swinging government-issued wooden clubs. In mandatory anti-terror drills conducted under police supervision, they fight off imaginary knife-wielding assailants.

An ethnic Uighur man walks down the path leading to the tomb of Imam Asim in the Taklamakan Desert. A historic trading post, the city of Kashgar is central to China's "One Belt, One Road Initiative", which is President Xi Jinping's signature foreign and economic policy involving massive infrastructure spending linking China to Asia, the Middle East and beyond.

A man herds sheep in Xinjiang Uighur Autonomous Region. China's worst fears are that a large-scale attack would blight this year's diplomatic setpiece, an OBOR summit attended by world leaders planned for Beijing. Since ethnic riots in the regional capital Urumqi in 2009, Xinjiang has been plagued by bouts of deadly violence.

A woman prays at a grave near the tomb of Imam Asim in the Taklamankan Desert. Uighurs are a Turkic-speaking distinct and mostly Sunni Muslim community and one of the 55 recognized ethnic minorities in China. Although Uighurs have traditionally practiced a moderate version of Islam, experts believe that some of them have been joining Islamic militias in the Middle East.

Chinese state media say the threat remains high, so the Communist Party has vowed to continue its "war on terror" against Islamist extremism. For example, Chinese authorities have passed measures banning many typically Muslim customs. The initiative makes it illegal to "reject or refuse" state propaganda, although it was not immediately clear how the authorities would enforce this regulation.

Many residents say the anti-terror drills are just part of an oppressive security operation that has been ramped up in Kashgar and other cities in Xinjiang's Uighur heartland in recent months. For many Uighurs it is not about security, but mass surveillance. "We have no privacy. They want to see what you're up to," says a shop owner in Kashgar.

The most visible change is likely to come from the ban on "abnormal growing of beards," and the restriction on wearing veils. Specifically, workers in public spaces, including stations and airports, will be required to "dissuade" people with veils on their faces from entering and report them to the police.

Authorities offer rewards for those who report "youth with long beards or other popular religious customs that have been radicalized", as part of a wider incentive system that rewards actionable intelligence on imminent attacks. Human rights activists have been critical of the tactics used by the government in combatting the alleged extremists, accusing it of human rights abuses.

China routinely denies pursuing repressive policies in Xinjiang and points to the vast sums it spends on economic development in the resource-rich region. James Leibold, an expert on Chinese ethnic policy says the focus on security runs counter to Beijing's goal of using the OBOR initiative to boost Xinjiang's economy, because it would disrupt the flow of people and ideas.