Taiwan's Foxconn, the company that manufactures parts for Apple's iPhone, has been forced to shut down its Taiyuan plant after a massive brawl among workers, 40 of which have been injured.
Reuters reports the incident has started as a personal dispute in one of the plant's dormitories, escalating into a full-on brawl involving 2,000 people.
The Taiyuan plant employs about 79,000 workers. According to China's Xinhua News Agency, it took around 5,000 police to stop the fighting.
"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," said Foxconn in a statement.
Foxconn, the world's largest electronic components manufacturer, employs more than 1 million people in China.
The company -- and, subsequently, Apple and other companies that have their products manufactured at Foxconn -- became a subject of controversy due to reports of poor working conditions. A string of suicides in the company in 2010 prompted Apple, HP and Dell to investigate the company's business practices.