FORTY people were injured in a brawl which broke out at a Foxconn factory in north China's Taiyuan City on Sunday night.
Three are in a serious condition, but most of the others were only slightly injured, a government official in Taiyuan said yesterday.
The Foxconn Technology Group, which assembles Apple's new iPhone 5 and makes components for top global electronics companies, said the plant had been closed while an investigation was carried out.
It was not immediately clear how long the shutdown would last at the plant, which employs about 79,000 people.
"The plant is closed today for investigation," Foxconn spokesman Louis Woo told Reuters yesterday. "We want to offer enough time for workers to calm down."
The Taiyuan government official, however, denied media reports that there had been a halt in the plant's production work, and said the factory was still in operation yesterday, Xinhua news agency reported.
Police said workers began arguing over a personal matter at around 11pm on Sunday and the situation soon erupted into an all-out brawl involving around 2,000 workers. Pictures posted online showed windows and doors smashed and cars overturned.
Around 5,000 riot police were mobilized to quell the violence, Xinhua said.
An initial investigation found that workers from Shandong Province had clashed with others from Henan Province.
In a statement yesterday, Foxconn said the incident escalated from what it called a personal dispute between several employees in a privately managed dormitory, and was brought under control by local police at around 3am.
"The cause of this dispute is under investigation by local authorities and we are working closely with them in this process, but it appears not to have been work-related," Foxconn said.
Online comments, however, suggested the factory's security guards may have been to blame, Reuters said.
In a Weibo posting, Jo-Liang said four or five security guards beat a worker almost to death, while another user, Fan de Sa Hai, quoted a friend from Taiyuan as saying guards beat up two workers from Henan, which led other workers to set quilts on fire and toss them out of dormitory windows.
The unrest was the latest in a string of incidents at plants run by Foxconn, the trading name of Hon Hai Precision Industry Co and the world's largest contract maker of electronic goods.
Drawing attention as a supplier and assembler for Apple products, the Taiwan-based company has faced allegations of poor conditions and mistreatment of workers at its operations on China's mainland where it employs a total of about 1 million workers, and it has been spending heavily recently to improve working conditions and raise wages.
Foxconn does not confirm which of its plants supply Apple, but an employee told Reuters that the Taiyuan plant is among those that assemble and make parts for Apple's latest iPhone 5.
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