Several top FBI executives promoted by former Director Christopher Wray were told Thursday to resign or retire and that they will be demoted or reassigned if they don’t leave, according to one current and three former bureau officials.

At least six senior FBI leaders have been ordered to retire, resign or be fired by Monday, according to sources briefed on the matter, extending a purge that began last week at the Justice Department across the street from the FBI headquarters.

The ultimatum was unusual for the FBI and suggested that President Donald Trump is purging leadership at an agency he has harshly criticized.