ICE agents have been spotted in Maine communities including Portland, Westbrook and Lewiston over the last two days.

The Department of Homeland Security is calling the latest enforcement effort “Operation Catch of the Day.”

On Wednesday, Westbrook Mayor David Morse confirmed that immigration agents were in the city, referring to their tactics as “outrageous behavior.”

At a Wednesday press conference, Portland Mayor Mark Dion questioned the need to send ICE agents to the city but urged residents not to interfere in enforcement operations.

“While we respect the law, we challenge the need for a paramilitary approach,” Mayor Dion said. “This council doesn’t stand apart from our immigrant communities, we stand with them.”

In a social media post on Wednesday that included a photo of an ICE agent in the city, Lewiston Mayor Carl Sheline said “ICE’s terror and intimidation tactics have no place in our American democracy.”

According to reporting by the Associated Press, Secretary of State Shenna Bellows, a longtime opponent of President Donald Trump, said state officials received a request from U.S. Customs and Border Protection for confidential, undercover Maine license plates and decided against issuing them.

The licenses plates are used on unmarked vehicles, and Bellows said she wants more assurance they will be used appropriately.

Gov. Mills has also pushed back on the latest operation, saying aggressive enforcement actions that undermine civil rights are “not welcome.”

Portland Public Schools, the largest and most diverse school district in the state, said in a statement Wednesday that it conducted a “lockout” at two schools to prevent anyone from entering the building during the school day Tuesday because of concerns about ICE activity nearby.

ICE released the names of four people detained in Maine on Tuesday who face charges including aggravated assault and operating under the influence.

An ICE official told Fox News in an interview that the agency had identified more than 1,000 targets in Maine and arrested about 50 people on Tuesday.

The department says it’s targeting what it calls “the worst of the worst criminal illegal aliens.”