WASHINGTON — FBI agents who participated in investigations related to President Donald Trump have sued over Justice Department efforts to develop a list of employees involved in those inquiries that they fear could be a precursor to mass firings.

Two lawsuits, filed Tuesday in federal court in Washington on behalf of anonymous agents, demand an immediate halt to the collection and potential dissemination of names of investigators who participated in probes of the Jan. 6, 2021 riot at the U.S. Capitol as well as Trump’s hoarding of classified documents at his Mar-a-Lago estate in Florida.

The suits mark an escalation in a high-stake dispute that burst into public view on Friday with revelations that the Justice Department had demanded from the FBI the names, offices and titles of all employees involved in Jan. 6 investigations so that officials could evaluate whether any personnel action was merited.

Thousands of FBI employees were also asked over the weekend to fill out an in-depth questionnaire about their participation in those probes, a step they worry could lead to termination.

Responding to the Justice Department’s request, the FBI turned over personnel details of about roughly 5,000 employees but identified them only through their unique identifier code rather than by name, according to a person familiar with the matter who spoke on condition of anonymity to The Associated Press.

The scrutiny of career agents is highly unusual given that rank-and-file FBI agents do not select the cases they are assigned to work on, do not historically switch positions or receive any sort of discipline because of their participation in matters seen as politically sensitive cases and especially because there’s been no evidence any FBI agents or lawyers who investigated or prosecuted the cases engaged in misconduct.

But Trump, dating back to his first term as president, has long been furious at the FBI and Justice Department and sought to bend federal law enforcement to his will.

He was investigated as president by agents examining potential ties between his 2016 campaign and Russia, and then after the leaving the White House, faced new criminal inquiries into his efforts to overturn the 2020 election and his retention of top-secret documents. His efforts to overturn election results and his retention of those documents both resulted in indictments that were dismissed after he won the presidency in November.

A Justice Department spokesman declined to comment.