Jabil Circuit (JBL) was accused Thursday of several workers’ rights violations at a factory in China as controversy swirls over the tech supply chain.

China Labor Watch painted a somewhat gloomy picture of working conditions at a plant in Wuxi, China. The New York-based advocacy group said Jabil forced some workers to take as much as 110 hours of overtime in violation of the company’s corporate code of conduct and Chinese laws. Some of that overtime was also unpaid, according to the report.

Jabil was also accused of ethical issues, such as having workers stand for11 hours in a shift with only half-an-hour meal breaks in certain departments. Those breaks, the report said, were cut short because of the time it takes to get from the production floor to the cafeteria and back.

Another issue the report flagged was occupational safety hazards. A CLB investigator working undercover failed to receive proper protective gear for a week. Training was also said to be fairly rudimentary, and the report said “workers are encouraged to copy the answers from the trainers and do not actually understand the information.”

“We are troubled by recent allegations related to excessive overtime, unpaid overtime, and working conditions at our Wuxi, China site. An audit team is en route to Wuxi to thoroughly investigate these claims,” St. Petersburg, Fla.-based Jabil said in a statement to FOX Business.

Still, the report did highlight a handful of features at the Wuxi site that appeared to be in-line with or even better than similar facilities. For example, the air-conditioned cafeteria provides free meals to employees in what was described as a quick and efficient manner. Indeed, the report said “the workers interviewed were generally happy about the quality and quantity of food.”

Jabil produces a wide range of electronic components at more than 60 plants across 33 countries. The company reported revenues $17.2 billion in fiscal 2012. 

The report from CLB said the Wuxi factory is producing a part for Apple’s (AAPL) rumored low-cost iPhone. An Apple spokesperson could not be reached for comment on the matter.

The world’s biggest technology company has been working for years to apply its ultra-tight controls to its sprawling supply chain. It audits many contractors, and it makes public what it calls Supplier Accountability Reports. It wasn’t immediately clear whether Apple audited the Jabil facility. However, CLB accused Apple supplier Pegatron of abuses in July.

Jabil and Apple shares were little changed in mid-morning trading Thursday. 

Follow Adam Samson on Twitter @adamsamson.