Videos on Chinese social media that said they were filmed at the factory in the central city of Zhengzhou showed thousands of people in masks facing rows of police in white protective suits with plastic riot shields. One person was hit in the head with a club and another was taken away with his arms held behind his back.
Other videos showed protesters spraying fire extinguishers toward police.
Postings on social media said they were protesting unspecified contract violations.
The factory operator, Foxconn Technology Group, said earlier it was using “closed-loop management,” which refers to employees living at their workplace with no outside contact. That followed a walk-out last month by thousands of employees over complaints about inadequate anti-virus protection and a lack of help for coworkers who fell ill.
Apple Inc. warned earlier that deliveries of its new iPhone 14 model would be delayed due to anti-disease controls imposed on the Zhengzhou factory. The city government suspended access to an industrial zone that surrounds the factory, which Foxconn has said employs 200,000 people.
Foxconn, headquartered in Taipei, Taiwan, did not immediately respond to a request for information about the situation.
New reports earlier said the ruling Communist Party ordered “grassroots cadres” to fill in for Foxconn employees in Zhengzhou who left. The company did not respond to requests for confirmation and details about that arrangement.
Last month, hordes of Foxconn workers left the factory en masse to avoid COVID curbs. Videos circulating on social media showed workers carrying bags of belongings and leaving by foot, with some volunteers leaving food and water on the streets for the workers.
China is the only major country in the world still trying to curb virus transmissions through strict lockdown measures and mass testing, and the strategy is being tested by multiple outbreaks driven by fast-spreading omicron variants.
Protests have flared as the number and severity of outbreaks has risen across China, including in Beijing. Earlier this week, authorities reported several COVID-19 deaths, for the first time in six months.
The Chinese government said Tuesday that more than 253,000 coronavirus cases have been found in the past three weeks and the daily average was increasing.
Foxconn and the local government have promised higher wages and better working conditions to attract new workers to the factory.
Meanwhile, COVID curbs remain in place, with the factory stating that it would continue its “closed-loop” system to reduce risks of COVID-19 transmission.
The Foxconn facility in Zhengzhou can accommodate up to 350,000 factory workers, but it is not clear how many are currently employed by the factory. It is also unclear how many of them have left, or how many were affected by COVID-19 curbs implemented in the factory prior to their departure.
Zen Soo contributed from Hong Kong. AP news assistant Caroline Chen in Guangzhou, China, contributed.
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