Dozens were injured as a mob of over two hundred workers used batons, steel bars and machetes to attack Foxconn's Yantai factory. In this photo, Apple CEO Tim Cook is shown visiting a different Foxconn factory in 2012. Courtesy / Reuters

Almost exactly one year to the day since last September’s Foxconn riot, which involved nearly 2,000 workers and temporarily shut down the immense China factory, another massive fight broke out across two dormitory buildings in Foxconn’s Yantai factory in the Shandong province.

The fight reportedly began Thursday night during the Mid-Autumn Festival and escalated on Saturday, when more than 200 Foxconn workers from China’s Guizhou province began chanting “beat all that are from Shandong” and assaulted random passers-by wearing factory uniforms. According to a South Metropolitan report on Monday, the mob of 200-plus workers used batons, steel bars and machetes to damage dormitories, a cafeteria and an Internet café within Foxconn. The riot required military police intervention before being broken up, and was reportedly captured by cell phone videos and posted to China’s Internet. More than 100 people, a majority of whom were from the Guizhou province, were reportedly arrested.

Reports claimed over 27 workers had to be hospitalized, while a single report from MyDrivers.com said the riot has led to three deaths. Foxconn later acknowledged the incident via its official Sina Weibo account and said no one was severely injured, hospitalized or killed. The manufacturer said only 11 individuals had sustained minor injuries.

The violence at the Yantai plant should not affect business for Apple, as Foxconn was quick to point out that its Yantai plant has “no association” with the iPhone maker, but the factory does manufacture a diverse array of electronic components including DVD players and laptop computers. Foxconn is Apple's largest iPhone manufacturing contractor, but most production is carried out in Foxconn's sprawling campus informally known as "Foxconn City."

The relationship between Apple and Foxconn has been mired in controversy. Concerns about working conditions at Foxconn first arose in late 2009, when a string of employee suicides occurred at a plant in southern China, prompting Foxconn to install nets to discourage workers from jumping. The following year, Apple released its 2010 report on employment practices of its suppliers, but the memo only mentioned child labor as a growing issue. But then, after the death of Steve Jobs in late 2011, two sobering reports from The New York Times, in January 2012, and a detailed CNN interview with one overworked Foxconn employee named “Miss Chen” the following month forced Apple to increase its efforts to improve working conditions within Foxconn. Apple even joined the Fair Labor Association (FLA), becoming the first technology company to do so.

“No one has been more upfront about the challenges we face," Apple CEO Tim Cook said in a February 2012 email to his employees. "We are attacking problems aggressively with the help of the world's foremost authorities on safety, the environment and fair labor. It would be easy to look for problems in fewer places and report prettier results, but those would not be the actions of a leader."

But despite the increased attention to labor laws and violations, Chinese environmentalist and workers’ rights groups continue to accuse Foxconn and Apple’s other suppliers of violating major safety and environmental standards. Taiwan-based Apple supplier Pegatron was accused of withholding worker pay and ID cards in July, and U.S.-based Jabil Circuit was accused of inadequate prework training, excessive mandatory overtime hours and hiring discrimination.

In its annual supplier responsibility report released in January, Apple conducted 393 audits at all levels of its supply chain in 2012 -- a 72 percent increase from 2011’s 229 audits -- and averaged 92 percent compliance with its 60-hour workweek maximum. Apple was also the first technology company to join the FLA, which allowed the largest-scale independent audit in company history.

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