LOS ANGELES (CBS SF & AP) — U.S. Immigration and Customs Enforcement announced Friday that its agents have arrested 212 people in a five-day operation around the Los Angeles region.

Agents also served 122 notices to businesses that they will be audited to determine whether they are employing people who are in the country illegally.

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The agency said 88 percent of those arrested were convicted criminals.

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The raids triggered a protest late Thursday in downtown Los Angeles, where a Homeland Security van was blocked from entering the federal Metropolitan Detention Center.

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Police were called and a dispersal order was given, but there were no arrests.