Republicans on the House Judiciary Committee say they’ve heard from over a dozen whistleblowers alleging the FBI is purging employees with conservative viewpoints and are calling on a top agency official to speak to them about the allegations.

The request for an interview and the allegations – which also include the agency having revoked security clearances for whistleblowers who made protected disclosures to Congress – were made in a letter Thursday from Republican members of the House Judiciary Committee to the agency’s executive assistant director of Human Resources, Jennifer Moore.

“During the course of this investigation, we have received protected whistleblower disclosures that the FBI is engaging in a ‘purge’ of employees with conservative views by revoking their security clearances and indefinitely suspending these employees,” states the letter by Ohio Rep. Jim Jordan, the committee’s top Republican.