The Justice Department has abruptly rescinded job offers made to dozens of recent law school graduates who were to be placed in entry-level positions in its antitrust, criminal, civil rights, immigration and national security divisions, and at the F.B.I., according to people familiar with the situation.

The offers were made through the Attorney General’s Honors Program, which has functioned without controversy — or much notice — under presidents of both parties for decades. The program is the latest target of Trump political appointees intent on reversing even the most workaday decisions made by their predecessors.

Participants in the program, one of the oldest career development initiatives in the federal government, received their acceptance letters in November and December for career-track jobs set to last 24 to 36 months.

Many were informed in the last few days that the offers had been terminated, setting off a scramble to find new employment.

A spokesman for the Justice Department did not immediately respond to a request for comment.

The decision to rescind the offers is just the first in many moves that are expected to be made in the coming days geared at ridding the department of left-wing lawyers and freezing programs that select applicants using diversity rules — part of a departmentwide push to exert tighter control over who gets jobs, according to a person involved in the transition planning.

The program is open to recent law school graduates, or young lawyers who have spent a short time working in law firms or serving in judicial clerkships, fellowships or internships.

Of those accepted, 25 each were to be assigned to the antitrust and civil divisions and 10 were to work for the civil rights division, with more than a dozen placed in jobs at the criminal division, the F.B.I. and U.S. attorneys’ offices around the country, according to a program fact sheet.