Raids at meatpacking plants in six states last week started with an investigation in early March that uncovered a potential of 4,300 illegal workers, only a fraction of which have been caught, U.S. Attorney Matthew Whitaker said Wednesday.

Whitaker, the U.S. Attorney for the Southern District of Iowa, said that Immigration and Customs Enforcement agents began scrutinizing employment documents at the Swift & Co. meatpacking plants in Iowa, Colorado, Nebraska, Texas, Utah and Minnesota.

On Tuesday, Whitaker announced some of the firsts arrests resulting from the raids. He said 23 people taken into custody during a raid at a Swift plant in Marshalltown have been charged with identity theft and immigration violations. In addition, seven other previous Swift workers taken into custody earlier in December have been charged.

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Whitaker said 89 people had been taken into custody during the Marshalltown raid.

The number of people in Iowa now charged in violations is a small slice of about 1,300 people who were detained in six states during the raids last week. The nationwide figure is far smaller than the number of people targeted by federal agents, though, Whitaker said.

Among the 14,000 Swift employees at those plants, Whitaker said, agents had identified 4,300 people with questionable documentation.

Nationwide, about 199 people have been charged and are held in jails. The rest face a lengthy administrative procedure that could lead to deportation.

Whitaker said he initiated the six-state raid after the March document study uncovered 664 potential illegal aliens working at the Swift plant in Marshalltown.

"When that was brought to my attention by ICE, I determined that something had to be done," he said. "It started off a series of events that included a national organization of five other judicial districts, which ultimately set up the enforcement actions that happened last Tuesday."

Twenty-one of the individuals taken into custody during the Iowa raid are charged with making a false statement or claim that they were a U.S. citizen, use of false state identification documents, use of fraudulently obtained Social Security cards and false representation of a Social Security number.

Ten of those individuals also face charges of aggravated identity theft and one also has been charged with illegally re-entering the United States after deportation for an aggravated felony.

An additional person was charged with illegal re-entry after being deported and another is charged with illegal entry.

The charged individuals range in age from 18 to 48 and are identified as being from Quatemala, Mexico or El Salvador. They will be arraigned this week, Whitaker said.

The false statement and false state documents charges carry a maximum prison sentence of up to five years in prison upon conviction. Fraudulently obtaining a Social Security card carries up to 10 years in prison and aggravated identity theft carries two years.

Illegal entry after deportation of an aggravated felony carries 20 years and illegal entry, two years.

Those not charged with a crime remain in federal custody facing administrative deportation procedures.

Whitaker said federal authorities held several discussions with Swift to resolve the issue of illegal workers that would take them into custody and be the least disruptive to the meatpacking operations.

"We just could not agree to any plan that would address all our concerns and address their concerns," Whitaker said.

A telephone message left with Swift was not immediately returned Tuesday.

When asked if he believed some workers were tipped off and left before the raids, Whitaker said that would be speculation.

"All I know is that we did not encounter as many as we had expected when we went in there last week," he said.

ICE Special Agent in Charge Mark Cangemi said the investigation is ongoing and that more arrests and charges could be forthcoming.

"There's still a lot of folks out there that were former or present employees of Swift that we have an interest in," he said.

Both men declined to say whether charges against Swift would be filed.

"This is not the end to these types of operations. We will continue to work with ICE and develop plans," Whitaker said. "We'll see where this ends up and how we can actually make sure the immigration laws are enforced."

Cangemi said it would not be unusual for action to be taken against companies if criminal charges can be proven.

"Individual employers are held accountable when we have evidence of a criminal charge," he said. "This is not over yet."

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