"Serious legal violations and labor abuses" have been found at Samsung factories, according to a U.S.-based labor group.
The organization, China Labor Watch, released a report today detailing its investigations into eight factories in China, six of which were directly operated by Samsung, two of which made products for the electronics company but were run by suppliers.
Among the abuses found by China Labor Watch (CLW) at the factories were staff being "forced" to work 100 hours of overtime a month, unpaid hours and unsafe conditions.
The report says that workers at the eight factories also have to endure "standing for 11 to 12 hours while working, underage workers, severe age and gender discrimination, abuse of student and labor dispatch workers, a lack of worker safety, and verbal and physical abuse."
In addition, there is no internal method for workers to air grievances in order to rectify the problems, the group said.
"This sort of illegal and inhumane treatment is rampant among Samsung's factories and supply chain. We demand that Samsung immediately begin the process of rectifying these abuses. With profits of over $12 billion in 2011, we are confident that Samsung has the wherewithal to systematically improve labor conditions for its network of factories and supplier factories in China," the organization said in its report.
The investigation took place from May to August 2012, and examined factories in Tianjin, Weihai, Huizhou, Suzhou, and Shenzhen that manufacture items including cell phones, mobile displays and electronics parts.
Investigators posed as workers or interviewed members of staff outside of the grounds to gather information for the report.
The eight factories investigated by the labor group are staffed by around 24,000 workers. The report said that the base salary for employees at a printer salary owned by Samsung is approximately $250 a month, while a supplier factory making cell phone casings paid around $205.
At the time of writing, Samsung had not provided comment on the report.