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.

President Trump is continuing to shake things up in his first 100 days and Fox News has learned that he has told high ranking FBI officials to resign or lose their jobs.

Paul Abbate, who as the FBI's longtime deputy director had been expected to replace Director Christopher Wray on an acting basis, is retiring from the bureau, according to an email he sent to senior executives and obtained by The Associated Press on Monday.

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

These senior officials at FBI headquarters were responsible for overseeing top priorities for the bureau, including national security, criminal and cyber issues, the sources said.