On Friday, Public Eye, a Swiss watchdog group, released a detailed report that accuses the rising fast-fashion giant of violating Chinese labour laws. 

The group hired independent Chinese researchers to track Shein’s manufacturing and packing process in China and Europe.

In Guangzhou, the city where Shein is headquartered and where many of its suppliers are located, researchers were able to track down 17 Shein partners. They found some manufacturers were informal factories set up in residential buildings. Some also had barred windows and no emergency exits, according to Public Eye; conditions that violate Chinese labour laws.

“I don’t want to think about what would happen if a fire broke out there,” one researcher said.

Workers in Guangzhou also told the researchers they sewed for 12 hours a day, working about 75 hours a week, and only received one day off a month. At Shein’s packing facility in the city of Foshan, workers also said they worked 12 to 14-hour days and up to 28 days a month. Chinese labour laws state workweeks cannot exceed 40 hours, and overtime cannot exceed 36 hours per month. Workers must also receive one day off per week. 

Researchers were told many labourers that work for Shein suppliers are migrant workers from other provinces.

“Many are only in the city for a limited time, without their families and with no responsibilities other than to earn as much money as possible,” the report said. “One of the interviewees states that, in general, the wage per item of clothing is considerably lower here than in other places where he had worked. However, the quality expectations are not particularly high either.”

In an email to BoF, Shein said it “takes all supply chain matters seriously.”

“Upon learning of the report, we immediately requested a copy and when we receive and review the report, we will initiate an investigation,” Shein said. “We have a strict supplier Code of Conduct which includes stringent health and safety policies and is in compliance with local laws. If non-compliance is identified we will take immediate action.”

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Shein did not manage to acquire Topshop, but it could now be looking for other struggling retailers to cement its position as China’s leading exporter of ultra-fast fashion with global ambitions.