Foxconn Technology Group says it is investigating a factory it operates that makes Amazon devices, including Kindles, after an in-depth report by advocacy group China Labor Watch criticized its "appalling working conditions", including excessive hours and over-reliance on temporary workers.
Taiwan-based Foxconn, known formally as Hon Hai Precision Industry Co Ltd (2317.TW), is the world's largest contract electronics manufacturer and employs more than a million people.
The China Labor Watch found workers earn about £233 a month, less than half the national living wage of £530, calculated for China by the Asia Floor Wage Alliance.
Foxconn's Hengyang plant primarily manufactures Amazon products, including its Alexa-enabled speaker Echo Dot.
The report detailed findings from a nine-month investigation that ended in April, which found workers putting in more overtime hours than permitted by Chinese labour law (which limits overtime to 36 hours every month) in order to make ends meet.
"All workers are subject to long hours and low wages", the report stated. Foxconn is considering building a display-manufacturing plant in the USA, the value of which could exceed $7 billion.
Foxconn is taking the report seriously and is carrying out a full investigation of the areas raised by that report, . In some instances, dispatch workers toiled 14 days consecutively without a break.
Amazon said it has called on a supplier to clean up its act at a Chinese factory where a watchdog group says it observed harsh conditions and mistreatment of workers.
China Labour Watch used an investigator who reported on his month at the factory, talking of workings "slumped, exhausted over their workbenches".
The report alleged the Foxconn factory often exceeded the number of dispatch workers allowed, and those workers were asked to work ridiculous hours for less pay.
Amazon said it had discovered "two issues of concern" at the Foxconn factory in Hengyang earlier this year. The biggest violations surrounded the factory's use of "dispatch workers", which are temporary employees. The workers are also reportedly subjected to verbal abuse at Amazon's manufacturing facility.
Amazon said that it immediately requested an action plan to correct the issues and said that it was monitoring the responses by Foxconn and compliances with Amazon's Supplier Code of Conduct.
Meanwhile, Foxconn "works hard to comply with all relevant laws and regulations", according to the same Reuters report. It added that regular audits were carried out "and if infractions are identified, we work to immediately rectify them".