China’s Zhengzhou city has locked down some areas near Foxconn Technology Group ’s main iPhone manufacturing base in a move that could spell further trouble for Apple ’s supply chain. Local authorities announced late Friday they are placing some areas in the Zhengzhou Airport Economy Zone under quarantine effective immediately, according to a statement on its official WeChat account. People in the area will not be permitted to leave, according to the statement. MacBook supplies at risk after Quanta Computer halts production in Shanghai The Zhengzhou Airport Economy Zone is home to the world’s largest iPhone assembly plant, where staff have been ordered to undergo mandatory Covid-19 testing in recent days. Foxconn and Apple did not immediately reply to emailed queries about whether the lockdown will affect operations. The fresh controls mark a widening of curbs in China, which is battling its worst Covid-19 outbreak in the past two years. Major cities from Shanghai to Guangzhou have already imposed restrictions on their citizens, fuelling burgeoning anger against the government. Fellow Apple suppliers Pegatron Corp and Quanta Computer have halted production in eastern China to comply with local Covid-19-related restrictions.