The FBI analyzed the cellphone “tolling data” of nine Republican lawmakers as part of its 2023 probe into the Jan. 6 Capitol riot, GOP senators revealed Monday.

The data, collected under the “Arctic Frost” investigation, focused on call metadata—who was called, along with time, date, and duration—but did not include call content.

Lawmakers identified include Sens. Ron Johnson, Lindsey Graham, Bill Hagerty, Josh Hawley, Dan Sullivan, Tommy Tuberville, Cynthia Lummis, Marsha Blackburn, and Rep. Mike Kelly, NBC News has reported.

Senate Judiciary Committee Chair Chuck Grassley criticized the collection as a violation of privacy and warned of potential consequences, while FBI Director Kash Patel vowed the bureau would no longer be “weaponized against the American people.”

The revelation has drawn bipartisan attention, with Senate Majority Leader John Thune expressing “grave concerns” and supporting further investigation into the matter.