MINNEAPOLIS (AP) — Half the workers at a janitorial company operating in the Twin Cities are being fired because they failed to provide documents proving they were legally in the U.S., according to their union.

The 240 employees at Harvard Maintenance would be dismissed by the end of the month, said Christopher Nulty, spokesman for the Service Employees International Union Local 26.

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The U.S. Department of Homeland Security notified the company it suspected some workers were illegal immigrants, and in December the company gave its employees 90 days to produce proper documentation, Nulty told Minnesota Public Radio News.

Two years ago, more than 1,200 janitors at ABM, another large commercial cleaning company in the Twin Cities, lost their jobs after a similar immigration audit.

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Javier Morillo, local president of SEIU, told MPR that the investigations of Harvard Maintenance and ABM didn’t fit with U.S. Immigration and Customs Enforcement’s stated goal of focusing on employers who knowingly hire and exploit unlawful workers.

“The janitors of the Twin Cities that are in the union, they’re not depressing wages for janitors,” Morillo said. “There are janitorial companies that pay much, much less that actually depress wages that are not being targeted for ICE audits.”

ICE said in a statement that it wouldn’t confirm or deny a possible ongoing investigation. Harvard Maintenance of New York did not return two calls seeking comment Tuesday.

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