Rong Shi in VOA's Mandarin service contributed to this report.
Amazon says it is investigating claims of worker abuse at a factory in China after a labor rights group found teenage employees at the factory were required to work night shifts and overtime hours for low pay.
The report by the New York-based group, China Labor Watch, found the factory, used by Amazon's hardware supplier Foxconn, relied on 1,500 student interns between 16 and 18 years old to work overtime and night shifts. The group said the practice is illegal under Chinese labor law, which sets limits on the time and conditions under which teenagers can work.
The executive director and founder of China Labor Watch, Li Qiang, told VOA, "Amazon and Foxconn should allow independent agencies to monitor the working environment of the related factories. Only in this way can violations of labor laws be prevented and effectively solved."
The report also said student intern workers at Foxconn's Hengyang factory in eastern China receive lower wages and fewer benefits than non-student workers. It said about 20% of workers at the factory are student interns, double the legal limit.
The plant makes popular Amazon devices, including Echo, Kindle and tablets.
"We are urgently investigating these allegations and addressing this with Foxconn at the most senior level," Amazon said in a statement, adding, "We do not tolerate violations of our Supplier Code of Conduct."
Foxconn acknowledged the issue in a statement Friday, saying it is increasing the monitoring of its internship program with schools "to ensure that, under no circumstances, will interns [be] allowed to work overtime or nights."
"There have been instances in the past where lax oversight on the part of the local management team has allowed this to happen and, while the impacted interns were paid the additional wages associated with these shifts, this is not acceptable and we have taken immediate steps to ensure it will not be repeated," the company said.
Foxconn, which is based in Taiwan, is the world's largest contract electronics manufacturer, employing more than a million people in China.
The company, which also makes Apple iPhones, came under the spotlight in 2010 following a spate of suicides at its plants in China, which activists blamed on poor working conditions.