China’s “COVID-zero” policy has led to numerous lockdowns, supply-chain nightmares, and the slowing of its economy.

But the country is sticking with it. And after several COVID cases were reported by Bloomberg, China is locking down the largest iPhone manufacturing plant in the world for seven days to try to curb the spread of the disease, Bloomberg reported Wednesday after the local government announced it over WeChat. 

The lockdown announcement comes days after reports that several workers have fled for fear of getting trapped. One worker identified by Zhuo by the Washington Post said that he and 200 other people made a break for it while the company was still operating as a “closed loop,” or contained bubbles to minimize virus exposure, but not fully locked down. He climbed a seven-foot wall and walked several miles before someone gave him a ride home. 

Foxconn quadrupled daily bonuses for those deployed at the factory to 400 yuan ($55) a day from 100 yuan in an effort to get them to stay, Reuters reported Tuesday, citing Foxconn’s official WeChat account.

The factory employs 200,000 people, earning it the nickname “iPhone city,” and workers who test positive for COVID will be forced into mandatory isolation, Bloomberg reported.

The area near Foxconn Technology’s plant in Zhengzhou has been cleared of vehicles and people who were not medical or other essential workers. The city reported 359 cases on Tuesday—a threefold jump from a day earlier.

A lockdown means that Foxconn employees will not be allowed to go in and out of the factory for work until at least Nov. 9. The plant will continue to operate in a bubble, according to Bloomberg. However, it is unclear how Foxconn will facilitate production with fewer workers than usual.

Foxconn did not immediately return Fortune’s request for comment.

The Taiwanese company Hon Hai Precision Industry owns the Zhengzhou plant, which alone produces four out of five of Apple’s most recent iPhone models.

The lockdown will likely hurt the production and shipment of iPhones in the lead-up to the holiday season. In September, Apple also launched its new line of handsets, the iPhone 14. During its fourth-quarter earnings call last Thursday, the company said the supply for its new model was constrained. The upcoming holidays will be critical for Apple as more consumers seek to buy gadgets at this time of year.

To address the gap in supply, Foxconn is reportedly increasing production at another factory in Shenzhen, according to Reuters. It has implemented closed loops to minimize virus exposure in March and July this year at another factory location in China.

Workers have been frustrated with the strict measures; many have taken to social media to talk about it. Foxconn denied rumors about the death of its employees in its dormitory, Bloomberg reported Tuesday.