Uniqlo and Skechers are among a group of fashion brands being investigated by French prosecutors over accusations that they have ignored China’s alleged abuse of Uighur muslims in the Xinjiang region.

It was confirmed on Friday that the investigation concerned Uniqlo France – owned by Fast Retailing – Inditex, which owns Zara and Bershka, SMCP, the owner of the French fashion labels Sandrop and Maje, and the footwear company Skechers.

The investigation is looking into accusations that the four brands had been concealing and profiting from crimes against humanity in China’s Xingjiang region by sourcing goods produced using the forced labour of Uighur muslims.

According to the investigative website, Mediapart, the investigation follows a complaint filed in early April by campaigners including the anti-corruption group Sherpa, the Uighur Institute of Europe, and a Uighur who was interned in Xinjiang.

Inditex has issued a statement rejecting the claims of the legal complaint and said it would cooperate fully with the investigation. 

“At Inditex, we have zero tolerance for all forms of forced labour and have established policies and procedures to ensure this practice does not take place in our supply chain,” it said.

SMCP also said it would cooperate with French authorities, but would prove the allegations to be false, stating that it “works with suppliers located all over the world and… does not have direct suppliers in the region mentioned in the press.”

Charged Retail writes that major fashion labels like Nike, H&M, and Burberry have been subjected to boycotts in China after denouncing the use of cotton from the controversial region of Xinjiang which makes up around 80 per cent of the country’s cotton output.

The issue of China’s treatment of Xinjiang’s mainly Muslim, Turkic-speaking minority, making up just under half of the western region’s 25 million inhabitants, has become a major source of diplomatic conflric between Beijing and the west, writes The Guardian.

While China denies all allegations of abuse in the region, UN experts and rights groups estimate that over a million people, mainly Uighurs and other Muslim minorities, have been detained in recent years in a system of camps in Xinjiang.

China has stated that these camps are ‘vocational training centres’ aimed at combating extremism, while rights groups say they have been used as a source of low-paid forced labour.

The Tokyo-based Fst Retailing has said it had not yet been contacted by French authorities but would cooperate fully to “reaffirm there is no forced labour in our supply chains,” while Skechers told Reuters it did not comment on pending litigation.

Uniqlo has not yet released a statement regarding the impending investigation.