Chicago, Illinois - Donald Trump's border czar on Sunday defended raiding churches and schools as part of a crackdown on undocumented immigration, while his office announced a multi-agency federal sweep aimed at "potentially dangerous criminal aliens" in Chicago.

Trump began his second term last Monday with a flurry of executive actions aimed at overhauling US immigration.

His administration quickly moved to ramp up deportations, including by relaxing rules governing enforcement actions at "sensitive" locations such as schools, churches, and workplaces.

Asked about the rule change, Tom Homan, who was tapped to oversee Trump's hard-line immigration agenda, said Sunday it sends a clear message.

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"There's consequences of entering the country illegally. If we don't show there's consequences, you're never going to fix the border problem," Homan, who is the former head of US Immigration and Customs Enforcement (ICE), told ABC News's This Week program.

Such actions would nonetheless be made on a "case by case" basis, he said.

If there's a "national security threat or a public safety threat that's in one of these facilities, then it should be an option," he said.

Homan was speaking from Chicago, a Democratic stronghold and a so-called "sanctuary city" for migrants, which he has called "ground zero" of the deportation push.

ICE announced Sunday on X that it had joined five other federal agencies in "enhanced targeted operations" in Chicago "to enforce US immigration law and preserve public safety and national security by keeping potentially dangerous criminal aliens out of our communities."

Joining ICE were the FBI; the Bureau of Alcohol, Tobacco, Firearms, and Explosives; the Drug Enforcement Administration; Customs and Border Protection; and the US Marshals Service.

No details were provided on the extent of the action or how many people were detained.

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Fear of being swept up in the raids kept many Latinos living in the region at home, the Chicago Tribune reported.

Illinois Governor JB Pritzker, a Democrat, told CNN that state officials would assist federal law enforcement agencies in apprehending anyone accused or convicted of violent crimes but would defend "law-abiding" citizens.

On Thursday, leaders of three Catholic organizations blasted the rule change that allows raids on churches and schools, saying in a joint statement that "turning places of care, healing, and solace into places of fear and uncertainty... will not make our communities safer."

When pressed on the Catholic opposition, Homan stood firm.

"We're enforcing laws Congress enacted, and the president signed. If they don't like it, change the law."

Vice President JD Vance, who was also asked about the Catholic pushback in an interview broadcast Sunday, accused one group of being worried about losing funds in the immigration crackdown.

"I think that the US Conference of Catholic Bishops needs to actually look in the mirror a little bit and recognize that when they receive over $100 million to help resettle illegal immigrants, are they worried about humanitarian concerns? Or are they actually worried about their bottom line?" he told CBS's "Face the Nation."

All eyes during Trump's first week in office have been on immigration enforcement and deportations, though it was unclear to what extent actions have increased from predecessor Joe Biden.

ICE said in posts on X that it had made 593 arrests on Friday and 286 arrests on Saturday.

In the 2024 federal fiscal year, agency data shows ICE made 113,431 arrests, or around 310 per day.

Homan called on Congress to pass additional funding for dealing with those arrested.

"We're gonna need more ICE beds, a minimum of 100,000," he told ABC News. "We're going to try to be efficient. But with more money we have, the more we can accomplish."