The UK fashion retailer Boohoo is under pressure to explain how an unofficial supplier was making clothes for the company while paying workers in a Leicester factory less than the minimum wage.

An undercover operation by The Sunday Times  newspaper reported that the factory, operating as ”Jaswal Fashions,” was also open when the English town of Leicester was under a local coronavirus lockdown, without extra health measures in place.

Boohoo says that Jaswal is “not a declared supplier and is also no longer trading as a garment manufacturer.”

“It therefore appears that a different company is using Jaswal’s former premises and we are currently trying to establish the identity of this company,” it says, adding that it would ban suppliers from working with the unknown firm.

“We will not hesitate to immediately terminate relationships with any supplier who is found not to be acting within both the letter and spirit of our supplier code of conduct.”

Workers were paid as little as £3.50 (€3.9-$4.4) an hour making garments under the firm’s Nasty Gal label, the report stated. The UK’s minimum wage for those aged 25 and over is £8.72 (€9.6-$10.9).

Boohoo is owned by Mahmud Kamani, who is set to scoop a £50 million (€55.2m-$62.5m) bonus under a new management incentive plan announced last month.