The Trump administration is preparing for a surge in increased immigration enforcement operations in Chicago next week, multiple law enforcement sources told ABC News.

The administration is preparing to expand on the operations in Los Angeles and potentially increase the law enforcement footprint, according to the sources. The operations could start as soon as Sept. 5, the sources said.

A DHS official told ABC News that the DHS is "going to make our streets and cities safe again."

"Across the country, DHS law enforcement are arresting and removing the worst of the worst, including gang members, murderers, pedophiles, and rapists that have terrorized American communities," a senior DHS official said.

--ABC News' Luke Barr

President Donald Trump revoked Secret Service protection for Kamala Harris on Thursday, according to a copy of the letter reviewed by ABC News.

The Executive Memorandum was issued Thursday afternoon by Trump, who sent it to Department of Homeland Security Secretary Kristi Noem, according to a senior official.

"You are hereby authorized to discontinue any security-related procedures previously authorized by Executive Memorandum, beyond those required by law, for the following individual effective September 1, 2025: Former Vice President Kamala D. Harris," the White House memorandum to Noem states.

Former President Joe Biden extended Harris' protective detail an additional year, on top of the six months she is required, by law, to have a Secret Service detail as the former Vice President, according to multiple officials.

This is just the latest protection detail that Trump has canceled early. In March, he canceled former Secretary of Homeland Security Alejandro Mayorkas' detail, along with the details of the Biden children, John Bolton and former Secretary of State Mike Pompeo.

"The Vice President is grateful to the United States Secret Service for their professionalism, dedication, and unwavering commitment to safety," Kristen Allen, a senior advisor to Harris said in a statement to ABC News.

--ABC News' Rachel Scott and Luke Barr

Trump also signed a memo directing Attorney General Pam Bondi to investigate whether federal grant money is being used to "support lobbying activities."

A fact sheet about the memo provided by the White House pointed to a couple of examples it claims violated the law.

The examples included a National Institutes of Health grant that allegedly "adapted an LGBTQ+ teen pregnancy prevention program for 'transgender boys'" and a U.S. National Science Foundation grant that was allegedly aimed at "advancing racial justice in elementary mathematics."

-ABC News' Isabella Murray and Michelle Stoddart

Trump signed an executive order on Thursday that ends collective bargaining with federal unions for agencies that focus on intelligence or national security work.

The White House argued in a statement that "procedural requirements" within unions create delays in agency operations.

The affected agencies include NASA, the National Weather Service, the National Environmental Satellite, Data, and Information Service (NESDIS), each part of the National Oceanic and Atmospheric Administration, the Hydropower Facilities in the Bureau of Reclamation Office of the Commissioner of Patents, the Patent and Trademark Office and the U.S. Agency for Global Media (USAGM).

-ABC News' Isabella Murray and Michelle Stoddart