Trump Administration Shocks Senior F.B.I. Ranks by Moving to Replace Them

A handful of senior F.B.I. employees have been told to resign in a matter of days or be fired, as the Trump administration moves to shake up the agency’s upper ranks, according to people familiar with the discussions.

The steps came as Kash Patel, the president’s nominee to lead the agency, sought to assure lawmakers during a contentious, hourslong Senate confirmation hearing that he would not begin a campaign of retribution or look backward by pursuing perceived rivals. It is unclear whether he was informed of the decisions, which were disclosed on the condition of anonymity to describe personnel matters.

The employees given the apparent ultimatum had been promoted under Christopher A. Wray, who stepped down as F.B.I. director this month.

In an email to colleagues, one of the senior agents said he had learned he would be dismissed “from the rolls of the F.B.I.” as soon as Monday morning.

“I was given no rationale for this decision, which, as you might imagine, has come as a shock,” he wrote.

Senior F.B.I. agents had been bracing for potentially swift changes under President Trump given Mr. Patel’s past promise to reshape the institution. He has vowed to empty out the F.B.I. headquarters building and turn it into a museum.