Two Freedom Caucus Republicans asked the Justice Department’s inspector general Monday to investigate allegations that Deputy Attorney General Rod Rosenstein threatened to subpoena the email and phone records of House Intelligence Committee staff.

Freedom Caucus Chairman Mark Meadows of North Carolina and caucus co-founder Jim Jordan of Ohio made the request in a letter to Inspector General Michael Horowitz, which alleges Rosenstein threatened the subpoenas in a tense January meeting about oversight requests from committee Republicans.

The Freedom Caucus leaders said two unidentified witnesses of the incident can provide documentation and sworn statements attesting to the encounter, which they say concerned oversight requests the committee sent to the department.

“This notion Mr. Rosenstein threatened to use his official investigative powers as Deputy Attorney General to retaliate against rank-and-file staff members for sending written oversight requests raises concerns he has abused his authority in the context of this investigation,” they write in the letter.

Filing a resolution to impeach Rosenstein “is an option being considered, as it has been for weeks,” a Meadows spokesman said.