Also indicted by a federal grand jury in Salt Lake City were a Utah woman and a Texas man suspected of providing the documents to some of the defendants, who are among the workers detained Dec. 12 in a raid on Swift & Co. Federal prosecutors put the number of detainees at 154.

Brett Tolman, the U.S. attorney for Utah, said the cases are among the more serious identity theft crimes. Many of the defendants allegedly had copies of birth certificates, driver licenses and corresponding Social Security numbers of citizens - not fake documents.

"It's not just a situation where individuals used false documents to gain employment," Tolman said. "This is the assumption of a citizen's identity."

Twenty-two others picked up in the raid are being prosecuted on state charges, such as forgery, by Cache County officials. Authorities also are considering presenting another 57 cases for possible state prosecution.

U.S. Immigration and Customs Enforcement will handle the cases of immigrants who are in the United States illegally and have no serious previous crimes on their records administratively, deporting them to their home countries.

Federal agents backed by local law enforcement made a sweep on Dec. 12 of Swift plants in six states as part of an identity-fraud investigation, picking up about 1,300 people.

The 15 Swift employees who were indicted in Utah are charged with various counts of aggravated identity theft, which carries a two-year mandatory minimum prison term that must be served consecutively to any other sentence; use of unlawfully obtained documents for employees, up to 10 years behind bars; use of false identification for employment eligibility verification, five-year maximum; identity theft, 15 years; and false use of a Social Security number, five years.

In addition, some sare charged with unauthorized re-entry of a deported alien, which has a maximum punishment of between two and 20 years in prison depending on prior felony convictions.

The two accused of selling documents - Veronica Carrillo, 41, of Logan, and Eleuterio Gutierrez, 48, of El Paso, who did not work for Swift - were indicted on two counts each of sale of citizenship papers and aggravated identity theft. Punishment for the sale charge is a maximum 10-year prison term.

Carrillo, a Mexican citizen, is in custody.

Gutierrez, a U.S. citizen, is a fugitive who is believed to be hiding in Texas or Mexico.

Tolman said the two are key figures because they facilitated the identity fraud of the other defendants.

"I felt it was very important to get at the heart of where the problem is," he said.

pmanson@sltrib.com