Fast-fashion giant Shein said it discovered two cases of child labor in its supply chain last year.

In its annual sustainability report, Shein disclosed this week that it found minors under age 15 employed by manufacturers that make products for the company. Shein, which mainly sources its products from China, did not say where it found the child labor cases.

The company said it suspended product orders from the suppliers when it discovered the violations. Both cases were resolved "swiftly" and involved remediation steps, such as ending contracts with underage employees and paying them any outstanding wages, Shein said. The online retailer resumed working with the manufacturers after they beefed up screening for new hires.

The disclosure comes as some advocacy groups - such as Amnesty International UK - are pushing back on a possible listing of Shein on the London Stock Exchange due to labor and environmental concerns.

The company, which was founded in China but is now based in Singapore, had also reportedly attempted to file a confidential IPO application to the U.S. Securities and Exchange Commission last year.

Shein said in its report that it updated its policies around labor violations in October 2023.

Before, suppliers engaging in practices like child or forced labor had their orders suspended and were given 30 days for remediation. Now, the company says it will "immediately proceed to terminate" ties with suppliers who engage in these violations.