China’s attempts to stamp out COID-19 are creating big strains on one of the country’s crucial manufacturing operations. Apple supplier Foxconn Technology is scrambling to contain a weeks-long COVID-19 outbreak at an iPhone factory in central China. 

The Wall Street Journal reports the disruption is growing at Foxconn’s main Zhengzhou facility, the world’s biggest assembly site for iPhones. Hundreds of thousands of workers there have been placed under a closed-loop system for almost two weeks, largely shut off from the outside world. Many said they have been confined to their quarters for days and that distribution of food and other essentials has been chaotic. 

The disruption at Foxconn is the latest example of the economic and social toll from China’s rigid pandemic policies, including rolling lockdowns and mass testing.

The turmoil now threatens to reach one of the world’s high-value, high-stakes supply chains.