(AP Photo by The Gazette, Jonathan D. Woods) In this July 3, 2008, file photo, escorted by U.S. Marshalls, Juan Carlos Guerrero-Espinoza, left, in white, and Martin De La Rosa-Loera, center, in green, walk into the U.S. Federal Courthouse in Cedar Rapids. Guerrero-Espinoza, a supervisor arrested after a massive immigration raid at the Agriprocessors plant in Postville, Iowa, is expected to plead guilty on Wednesday Aug. 20, 2008, to charges he knowingly hired illegal immigrants, according to court filings.

DES MOINES -- A supervisor arrested after a massive immigration raid at the Agriprocessors plant in Postville is expected to plead guilty on Wednesday to charges he knowingly hired illegal immigrants, according to court filings.

Juan Carlos Guerrero-Espinoza is expected to plead guilty to charges he conspired to hire illegal immigrants and aided and abetted the hiring of illegal immigrants.

The U.S. Attorney's Office for the Northern District of Iowa filed additional charges against Guerrero-Espinoza on Tuesday. In a letter filed with the charges and addressed to Judge Jon S. Scoles, U.S. Attorney Matt M. Dummermuth wrote that Guerrero-Espinoza is expected to waive his indictment and enter into a plea agreement.

A hearing is scheduled for 1:30 p.m. at U.S. District Court in Cedar Rapids on Wednesday.

Phone messages left with Guerrero-Espinoza's lawyer, John L. Lane, and Martin De La Rosa-Loera's lawyer, Jill M. Ableidinger, were not immediately returned.

Bob Teig, a spokesman for the U.S. attorney's office, said he could not comment beyond court filings.

According to Tuesday's court filings, on May 7, 2008, Guerrero-Espinoza told employees that he supervised that they would be fired and immediately rehired, and that he knew they were unauthorized to work in the United States.

Court documents allege that, over a one year period, Guerrero-Espinoza conspired to hire 10 more individuals who were in the country illegally.

Last month, 35-year-old Guerrero-Espinoza and 43-year-old Martin De La Rosa-Loera were charged with encouraging illegal immigrants to reside in the U.S. and aiding and abetting the possession and use of fraudulent identification.

Guerrero-Espinoza also last month was charged with aiding and abetting aggravated identity theft.