Amazon contract manufacturer Foxconn has been accused of recruiting over 1500 underage interns from local vocational schools to work on Amazon’s Echo smart speaker. These interns were forced to work overtime and night shifts, which is against local laws, and were being paid less than regular workers.

The accusations were made this week in a new report by China Labor Watch, which also said that the company pressured its student interns to put in those extra hours. “If interns were unwilling to work overtime or night shifts, the factory would arrange for teachers to pressure workers,” the report states. “For interns who refuse to work overtime and night shifts, the factory requests teachers from their schools to fire them.”

Foxconn told The Guardian, which was first to report on the accusations, that these kinds of violations had occurred in the past. “There have been instances in the past where lax oversight on the part of the local management team has allowed this to happen,” the company said, while promising to take steps against such violations in the future. “This is not acceptable and we have taken immediate steps to ensure it will not be repeated,” the company said in its statement to the paper.

Amazon also said that it wasn’t going to tolerate these labor law violations, with a spokesperson telling media: “We are urgently investigating these allegations and addressing this with Foxconn at the most senior level. Additional teams of specialists arrived on-site yesterday to investigate, and we’ve initiated weekly audits of this issue.”

The China Labor Watch report in question highlights the working conditions at just one Foxconn factory, which employs just shy of 7500 workers. Altogether, Foxconn employs over 800,000 workers across mainland China, which assemble a wide variety of products from companies including Amazon, Apple, Google, Nintendo and others.

The company has faced accusations of labor law violations in the past, including reports that stressful working conditions and dire living situations in its company-run dorm rooms were causing a wave of suicides in 2010.

Foxconn is not alone with these problems, which ultimately point to a bigger issue: The consumer electronics industry’s practice to keep products secret until the very last minute, and then ship them on the day of a public unveil, forces manufacturers to use massive overtime cycles, with workers often pushing 60 hours or more.