(Reuters) - Several labor groups sued the Trump administration for allegedly firing tens of thousands of probationary employees illegally, as part of its drive to overhaul the federal government.

In a complaint filed on Wednesday night in San Francisco federal court, the groups said the Office of Personnel Management, which manages the federal civilian workforce, lacked authority to direct federal agencies on February 13 to fire the employees en masse, ostensibly for performance reasons.

The labor groups said Congress controls and authorizes federal employment and related spending by U.S. administrative agencies, and the Office of Personnel Management has no authority to fire federal employees other than its own.

"OPM, the federal agency charged with implementing this nation's employment laws, in one fell swoop has perpetrated one of the most massive employment frauds in the history of this country, telling tens of thousands of workers that they are being fired for performance reasons, when they most certainly were not," the complaint said.

The Office of Personnel Management on Thursday referred a request for comment to the Department of Justice, which did not immediately respond to a request for comment.

Probationary periods for federal employees typically last a year, but can run longer.

Trump and Elon Musk, who oversees the so-called Department of Government Efficiency, are spearheading an unprecedented effort to shrink the federal bureaucracy, including through job cuts.

The plaintiffs in Wednesday's lawsuit include the American Federation of Government Employees (AFGE); the American Federation of State, County and Municipal Employees; AFGE Local 1216 in San Francisco, and the United Nurses Associations of California/Union of Health Care Professionals.

They are seeking to set aside the February 13 directive, and rescind the firings of probationary employees.