Amazon warehouses are beginning to see their workforce thinned by the Trump administration’s revoking of a Biden-era program that allowed immigrants to live and work legally in the United States. Hundreds of workers at an Amazon building in West Jefferson, Ohio, which employs more than 3,700 people, recently lost their jobs, and the problem is spreading across the country, reports the New York Times.

Raids to catch workers who are not legally allowed to work in the U.S., in fields and Home Depot parking lots, have grabbed media attention, although these seem at odds with the administration’s commitment to deport illegal immigrants who are violent criminals, not ordinary workers. But now, the Times reports, thousands of foreign workers across the country with legal status have been swept up in a quiet purge.

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On May 30, the U.S. Supreme Court granted temporary approval for the Trump administration to revoke a program known as “humanitarian parole,” which had allowed more than 500,000 migrants who were victims of political turmoil in their home countries of Cuba, Haiti, Nicaragua and Venezuela to quickly get work permits if they had a fiscal sponsor.

Immigrants account for 21% percent of workers in warehousing, distribution, and fulfillment, according to the Center for Migration Studies of New York. According to the American Immigration Council, illegal immigrants constituted 5.4% of the workforce in transportation and warehousing in 2020, or 460,000. A low estimate therefore means that some 1.2 million immigrants who work in transportation and warehousing do so purely at the discretion of U.S. immigration policy. That policy is now radically changing.

In late June, Amazon began asking staffers who came to the U.S. under the Biden-era program to provide updated work permits within a certain time-frame, or they would be put on unpaid leave, according to documents viewed by CNBC.

According to CNBC, Amazon is far from alone. Other companies including Walmart and Disney have been forced to fire employees or put them on leave in order to comply with shifting federal policies. Amazon has declined to say how many workers were affected.

“We’re supporting employees impacted by the government’s recent changes in immigration policy,” Richard Rocha, an Amazon spokesman, said in a statement. The company says it has pointed workers to various resources, including outside free or low-cost legal services.