The immigration blitz was action long promised by President Donald Trump who made mass deportation central to his campaign.

The agents turned out to be unrelated to immigration, officials said hours later. They were from the Secret Service, investigating a threat.

The Trump administration revoked a policy that prohibited arrests by U.S. Immigration and Customs Enforcement agents at or near schools, places of worship and other places deemed to be "sensitive locations.

The sheer number of federal agencies involved showed President Donald Trump’s willingness to use federal law enforcement beyond the Department of Homeland Security to carry out his long-promised

Law enforcement agents attempted entry into a Chicago elementary school Friday morning, but were not allowed inside or permitted to speak to anyone inside, Chicago Public Schools officials said.

Enhanced immigration enforcement operations were reported in Chicago and parts of Illinois starting on Sunday and were expected to continue through the week as federal agencies touted arrests around the country.

A spokesperson for Immigration and Customs Enforcement said a range of federal agencies conducted "enhanced targeted operations" in Chicago on Sunday "to enforce U.S. immigration law and preserve public safety.

Trump border czar Tom Homan and TV personality Dr. Phil are in the city to observe the operations, according to reports.

Ryan Walters said he would help the Trump administration in “any way they see fit” to carry out immigration enforcement.

Chicago Public Schools officials had initially said the agents were from U.S. Immigration and Customs Enforcement. Secret Service said they were investigating a threat, and responded to a house.

Chicago school officials claimed several Immigration and Customs Enforcement agents tried to enter a majority-Latino elementary school in the south side of Chicago on Friday, days after Donald Trump ’s administration rescinded long-standing policy that prohibits law enforcement actions in schools and churches.