“It is D.H.S.’s understanding that the Department of the Treasury has qualified law enforcement personnel available to assist with immigration enforcement, especially in light of recent increases to the Internal Revenue Service’s work force and budget,” Ms. Noem wrote.

The request comes as Trump boasts about curtailing the IRS, whose agents focus on tax violations and other financial crimes.

The U.S. Department of Homeland Security wants to deputize some Internal Revenue Service criminal investigators and other Treasury Department personnel to perform immigration enforcement, according to a DHS document and an agency spokesperson.

Although the Internal Revenue Service has the responsibility of collecting taxes, some members of the department could soon have more duties added to their roles. U.S. Homeland Security Secretary Kristi Noem asked the Department of the Treasury to deputize some law enforcement workers to assist with immigration enforcement in a memo obtained by the Wall Street Journal.