CHICAGO (CBS) — Federal immigration agents and police have arrested 29 reputed street gang members in the Chicago area, all but one of them foreign nationals.

It was part of a larger national crackdown.

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The big focus nationally was Honduran gangs involved in human smuggling and trafficking, but U.S. Immigration and Customs Enforcement Chicago Special Agent-in-Charge Gary Hartwig said the local focus was different — drug gangs, mostly Mexican.

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Hartwig said only one of the 29 is a U.S. citizen.

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“That individual was arrested in Waukegan and he had, at the time of his arrest and he’s a known gang member, had in his possession two assault rifles, an AR15 and an AK47, two handguns and a quantity of heroin and cocaine,” Hartwig said.

Only three of the 29 face new criminal charges. Hartwig said the rest are just being held on immigration violations, although he said that can be misleading.

He said one of those not criminally charged is a 47-year-old Venezuelan national who has “a significant prior criminal history” that includes drug distribution and unlawful weapons possession.

“He’s a good person for us to have off the streets of Joliet,” Hartwig said.

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Nationally, immigration officials reported, 479 of the 637 arrested were charged with federal criminal offenses, 210 of whom had violent criminal histories. Another 117 face state or local criminal charges.