Some of the U.K.’s biggest supermarket retailers have launched an investigation into the treatment of migrant fishers after the Financial Times uncovered allegations that migrant crew workers on British fishing vessels were being mistreated.

Many overseas workers in the British fishing industry are employed through an immigration “loophole,” according to the Financial Times, allowing boats that fish in international waters to not be considered part of the U.K. even though they operate out of British ports. During the June 2023 investigation into the “loophole,” Filipino workers on some Anglo-North Irish Fish Producers Organisation (ANIFPO) boats said they had been subjected to various types of mistreatment, including restricted access to medical care and forced labor.

The probe, which is being overseen by the Seafood Ethics Action Alliance, will analyze the conduct of ANIFPO, local boat operators and local boat owners. The investigation, beginning sometime during the week of July 10, will also examine “wider human rights reform” within the U.K. fishing sector.

The probe is being funded by seven supermarkets and business members of the Seafood Ethics Action Alliance, including Tesco, Asda, Morrisons and Whitby Seafoods, which represent roughly 95% of the U.K. seafood market.

“We’ve been working to ensure it’s a robust independent investigation,” said Andy Hickman, head of the Seafood Ethics Action Alliance. “The issues faced by the workers… aren’t unique to Northern Ireland. Alongside this investigation, it’s critical that we work with the fishing industry on a wider program of reform that addresses the root causes which contributed to the allegations.”

The Seafood Ethics Action Alliance said that it will support any attempts to implement necessary improvements to the U.K.'s fishing industry.