Electronics manufacturer Foxconn has admitted to hiring interns that are under China's legal working age.
Foxconn said that it performed an internal investigation at its Yantai facility in the Shandong Province and found that some of the interns working there were as young as 14, even though China's legal working age is 16.
"Our investigation has shown that the interns in question, who ranged in age from 14 to 16, had worked in that campus for approximately three weeks. This is not only a violation of China's labour law, it is also a violation of Foxconn policy, and immediate steps have been taken to return the interns in question to their educational institutions," said the company.
China Labor Watch said in statement that underage interns were sent to Foxconn by their schools, who should take primary responsibility. However, it insisted that Foxconn should have confirmed the ages of its workers.
Foxconn accepted blame and insisted that it will 'immediately' fire any employee found to have been responsible for the violations.
The Yantai case comes just a month after another Foxconn facility in the Jiangsu province in China was hit with charges that the company improperly put interns to work on the production line to make iPhone accessories, including USB cables.
However, Foxconn quickly denied that claim, saying that the Fair Labor Association, which is auditing Foxconn factories, "found no evidence that any interns were pressured to participate."
Foxconn has had a history of violating working practices in China. An FLA investigation into the company requested by Apple found numerous violations, including excessive overtime and improper pay.
It has long run internship programmes under which students work on the production lines for up to six months. It said that the interns make up approximately 2.7 per cent of its 1.2 million employees in China.
While Foxconn argues these programmes allow students to gain experience, labour activists have repeatedly accused it of exploiting the students and using the programme to make up for staff shortages.
Over the past two years, Foxconn has enacted many reforms at its factories, including steep pay rises, outsourced worker accommodation and reduced overtime in a bid to clean up its image.
In August, the Fair Labor Association said the company had fixed 284 of the 360 problems that it had previously identified.
The company's second-largest plant, in Zhengzhou, which makes the iPhone 5, was this month rattled by a dispute between quality control staff and line workers, and last month thousands of workers at the Taiyuan factory rioted after an argument between a worker and a security guard.
Earlier this year, workers at the company's Chengdu plant, which makes iPads, damaged facilities in a pay dispute. Meanwhile, hundreds staged a protest sit-in on the roof of a Foxconn factory in Wuhan.