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Dozens of unauthorized immigrants – most of them people who illegally re-entered the United States after having been deported -- are in detention in New Jersey following a week-long sweep by immigration agents.

Immigration officials said Thursday that they arrested 31 people in the sweep; 28 were formerly deported and re-entered the country illegally, which is a criminal offense. Three had immigration violations, which is a civil matter.

U.S. Immigration and Customs Enforcement, or ICE, officials said that 16 of the 28 who re-entered had prior criminal convictions. The convictions, officials said, included such things as assault, distribution of a controlled substance within 1,000 feet from a school zone, and weapons possession.

“ICE is focused on sensible, effective immigration enforcement that prioritizes efforts first on those dangerous criminal aliens and other immigration violators who present the greatest risk to the security of our communities,” said John Tsoukaris, ICE field office director in Newark. “Reducing crime at the street level and removing these individuals from the United States is a top ICE priority.”

New Jersey is among the top four states with the highest percentage – 6.2 percent -- of unauthorized immigrants, according to a recent Pew Hispanic Center report.

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Tsoukaris said when someone illegally re-enters after having been deported, “You’re looking at possible jail time, if we do a criminal prosecution, from two years to 20 years.”

“They violated the immigration laws again and came back,” he said.

Nearly half, or 11, of the people arrested were from Mexico.

The Mexican population in New Jersey has been growing steadily since the 1990’s, when many moved from California and many others began settling in the state directly from Mexico.

Mexicans make up the majority – 58 percent, or 6.5 million -- of the unauthorized population of roughly 11 million in the United States, according to the Pew report.

Others arrested in the New Jersey sweep were from Guatemala, Brazil, Peru, Honduras, the Dominican Republic, El Salvador, Portugal and Guinea. Those arrested included 25 men and six women, immigration officials said.

Elizabeth.Llorente@FoxNewsLatino.com

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