Churches across Chicago on Sunday urged calm resistance and practical precautions as residents prepared for an expected federal immigration enforcement operation and the possibility of a National Guard deployment.

The Rev. Marshall Hatch told congregants at New Mount Pilgrim Missionary Baptist Church on the city’s West Side to carry identification, keep family informed of their whereabouts and be prepared to protest. "You need to start telling people about your whereabouts, so you don’t disappear," Hatch said. "We’re not going to despair. We’re not going to feel threatened. We’re not going to give up and give in to fascism and authoritarianism."

Details about the scope and timing of the anticipated federal action remained sparse. The Department of Homeland Security has said it plans to use a military base north of the city and notified leaders in a suburb that it will use a federal immigration processing center there for an operation that could last as long as 45 days. Tom Homan, a former acting director of Immigration and Customs Enforcement who serves as a border czar in the Trump administration, told CNN’s State of the Union that federal law enforcement action would come to Chicago "this week" and that similar worksite enforcement operations could follow in other cities.

President Donald Trump has repeatedly threatened federal intervention in Democratic-run cities, most recently saying he could send significant federal resources to Chicago to address crime and increase deportations. The administration sued Chicago over its sanctuary policies and launched a nationwide immigration enforcement operation in the city in January. Local leaders and many residents have strongly objected, saying additional federal forces are unnecessary and risk inflaming tensions.

The anticipated intervention has raised particular concern among Black and Latino communities, where trust in law enforcement is fragile. Lester Burks, a 74-year-old U.S. Army veteran who attends New Mount Pilgrim, said a military presence would be threatening. "I don’t want soldiers here," he said. "They are trained to fight."

At a West Side news conference on Sunday, U.S. Rep. Danny Davis, a Democrat, criticized the idea of more federal personnel on city streets, saying, "We don’t need another level of law enforcement and their presence to pretend they’re going to solve problems related to violence." Democrats and local officials have pointed to long-term disinvestment and the need for resources as part of addressing violence; Hatch said the church was calling for resources, not a military response, and celebrated the groundbreaking of a nearby arts and activism center he said was part of a solution.

Clergy in immigrant-heavy neighborhoods have worked to calm fears while preparing congregants. Some churches reminded people of their rights when dealing with immigration agents and urged parishioners to carry necessary documents. The January operation had a chilling effect on attendance at immigrant and Latino churches, clergy said, and organizers feared a repeat as Mexican Independence Day celebrations were overshadowed by anxiety about enforcement.

The administration has already deployed the National Guard to Los Angeles and federalized the police force in Washington, D.C.; a federal judge has ruled the Los Angeles deployment illegal. Trump has also said he might send National Guard troops to New Orleans before Chicago. There is no single legal definition for "sanctuary" policies; the term generally refers to limits on local cooperation with Immigration and Customs Enforcement.

As Chicago awaited clearer information about the planned operation, church leaders and elected officials urged residents to remain informed, protect their rights and maintain community connections. Associated Press writer Calvin Woodward contributed reporting to the ABC News account.