Chinese authorities imposed lockdowns on 600,000 people in the area surrounding the world's largest iPhone factory on Wednesday, as workers complained of disorderly Covid controls at the facility.
All people except Covid-prevention volunteers and essential workers "must not leave their residences except to receive Covid tests and emergency medical treatment", officials from central China's Zhengzhou Airport Economy Zone said.
The move comes after images emerged on Chinese social media last week showing people breaking out of the facility, which is run by Taiwanese tech giant Foxconn and makes products for Apple.
Employees complained online of poor conditions, a lack of supplies and having to flee the factory on foot to avoid Covid transport curbs. Foxconn says there are currently more than 200,000 workers at its Zhengzhou plant.
"Being paid is not important anymore, the most important thing is to survive," one 30-year-old man working at Foxconn told AFP, saying he was staying at the factory because he was afraid of adding to an outbreak in his hometown.
"The anti-virus measures on campus are shambolic, virus-negative people are living together with virus-positive people," said the worker, who asked to remain anonymous.
He said the food provided to employees was "not filling", and complained of a lack of medicine for sick colleagues.
China is the last major economy committed to a zero-Covid strategy, persisting with snap lockdowns, mass testing and lengthy quarantines in a bid to stamp out emerging outbreaks.
But new variants have tested local officials' ability to snuff out flare-ups faster than they can spread, causing much of the country to live under an ever-changing mosaic of Covid curbs.
The district in Zhengzhou city said Wednesday that all businesses would be required to work from home, with only "key enterprises" allowed to continue operating. It did not specify which businesses fell under that category.
Only medical vehicles and those delivering essentials are allowed on the streets.
The district's more than 600,000 residents will have to take nucleic acid tests every day, the local government said, warning that it would "resolutely crack down on all kinds of violations".
The Communist Party-run Dahe Daily said on Wednesday local authorities would "thoroughly disinfect" Foxconn's facilities, including employee dormitories, over the next three days. Workers quarantining at the factory would need to show seven days of negative tests before leaving for their hometowns.
The paper also said the government had promised to provide timely meals and to set up a counselling hotline for workers.
