Apple said that an audit confirmed the hours worked, but the company denied that students were made to work against their will.
This "work experience" was a graduation requirement for the school, which meant the students were forced to labor if they wanted a diploma.
For her part, Yang assembled up to 1,200 iPhone X cameras in a shift.
An Apple representative told Quartz that the Financial Times' reporting is inaccurate and noted that the students participate in the internship voluntarily. "Unfortunately, there have been a number of cases where portions of our campuses have not adhered to this policy", Foxconn said in a statement, adding that the interns accounted for a small part of the workforce. We've confirmed the students worked voluntarily, were compensated, and provided benefits, but they should not have been allowed to work overtime.
Foxconn and Apple later took measures to try to make the factory more comfortable and to reduce the amount of overtime from employees, though there have been several reports of worker suicides since.
Foxconn and Apple have come under scrutiny for conditions and circumstances of labor in China before.
This is not the first time that both Apple and Foxconn have been criticised for its use of underage workers and excessive use of overtime. It is simply the abuse of working hours by making them work overtime that is breaking the law. Under Chinese law, children are prevented from working over forty hours a week.
There were six students in total who spoke to the publication, saying they were sent along with a group of 3,000 students from Zhengzhou Urban Rail Transit School in September to work at Foxconn's facility.
Apple said in its statement to Quartz that it "is dedicated to ensuring everyone in our supply chain is treated with the dignity and respect they deserve".