The European Center for Constitutional and Human Rights (ECCHR) filed a criminal complaint in  Germany on Monday accusing five retailers of using forced labor in Xinjing in their production line.

In a press statement by the ECCHR, information has found that companies including Lidl, Aldi, Hugo Boss, and others have “allegedly directly or indirectly abetted and profited from the forced labor of the Uyghur minority in Xinjiang.”

There have been mounting concerns over concentration camps in western China holding Uyghur Muslims, condemning them to forced labor in the cotton mills. While the Chinese government has referred to the centers as “vocational training institutions,” German companies that have suppliers in the region could be involved in crimes against humanity the ECCHR claim.

Companies such as Hugo Boss and Lidl have denied all allegations, ensuring fair working conditions in their supply chains. The director of the ECCHR, Saage-Maass, made clear though that the five companies listed in the criminal complaint are mere examples of a “wider and more systematic problem.” Investigations will rely on prosecutors looking into claims of international labor law violations, rather than information gathered by civil organizations.

This case follows in the footsteps of one filed against France in July. A French inquiry has been opened to look into allegations that Uniqlo and Zara have profited from similar forced labor in Xinjiang.