The Apple Inc. logo is seen in the lobby of New York City's flagship Apple store in this January 18, 2011 file photo. (MIKE SEGAR/REUTERS)

Apple said that underage workers were allowed to work at its supplier plants in China because labor agents in the country faked paperwork to make workers appear older than they were.

The company said Friday that it terminated its relationship with the supplier, Guangdong Real Faith Pingzhou Electronics Co., after discovering instances of underage workers.

The report says Apple also traced the source of the faked paperwork to a central third-party labor agent, called Quanshun. Apple said it has reported Quanshun — which worked with families to forge the paperwork — to local authorities and said the firm has had its business license revoked.

Bloomberg reported that a manager at the branch of Quanshan in the southern city of Shenzhen, Wu Yong, denied it had worked with the manufacturer to forge documents. The report also said that the company’s affiliate in the Henan province of central China had been de-registered in October.

Apple’s senior vice president of operations, Jeff Williams, also told Bloomberg that the company felt it was important to identify the suppliers to highlight the problem. In the past, Apple has not included the name of suppliers found to be violation of its policies — something that labor groups have criticized.

Apple reviewed 393 suppliers in its chain over the course of 2012 as part of its annual supplier responsibility report — a 72 percent increase from its previous report.

Overall, the company said that 79 percent of its suppliers are in compliance for its standards on worker practices, and 73 percent of suppliers met its standards for having management systems in place to prevent bad practices. That compares to compliance rates of 76 percent and 71 percent, respectively, in the company’s 2012 report.

Apple has been releasing supplier responsibility reports since 2007, but did not disclose even the names of its suppliers until it released its 2011 report in January of last year.

The company has faced criticism for labor practices at its supplier factories in the past, coming under harsh scrutiny after a rash of worker suicides in 2010 at one of its largest suppliers, Foxconn. Criticism increased after explosions at two Chinese factories in 2011.

In 2012, Apple announced that it had joined the Fair Labor Association, which conducts independent audits of the company’s facilities. In a report published in March, the FLA said it had found that problems with working conditions persisted at Foxconn plants. According to the report, more than half of the workers at the assembly facilities it visited worked in violation of labor laws that cap the working week at 60 hours.

Apple’s report Friday said that it found 92 percent of the facilities it visited were in compliance with work week limits, and that the average employee worked 50 hours per week.

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