According to an affidavit, “Based on information thus far developed in the investigation, it appears, based on 2007 fourth quarter payroll reports, that approximately 76 percent of the 968 employees of Agriprocessors were using false or fraudulent social security numbers in connection with their employment.”
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A total of 16 local, state and federal agencies, led by ICE, joined the investigation that began last October. Among them was the U.S. Marshals Service, the Iowa Department of Public Safety, the Federal Bureau of Investigations, the U.S.
Anonymous sources reported in raid warrants
According to search warrants, ICE agents interviewed a former plant supervisor – identified as “Source 1” – in November 2007, who told them that the plant employed foreign nationals from Mexico, Guatemala and Eastern Europe.
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The supervisors also described an encounter with the plant’s human resources manager about three separate Social Security cards from different employees with the same number. The human resources manager "laughed when this matter was brought to her attention," the supervisor told federal agents.
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A plant employee identified as “Source 11” told authorities that he/she was hired without presenting employment documents or filling out any forms. The worker’s first paycheck had a different person’s name on it, which was then cashed at another part of the plant.