LOS ANGELES (CNS) — A district director for Rep. Tony Cárdenas (D-Panorama City) confirmed on Tuesday, April 21, that she was subpoenaed by a Los Angeles federal grand jury that may be investigating campaign activities of the congressman’s staff, it was reported.

Gabriela Marquez, who heads operations in Cárdenas’ Panorama City office, formally notified the House of Representatives on April 16, and the notice was read into the record in accordance with House rules, according to Roll Call, the Washington, D.C., publication covering Capitol Hill.

 A representative for Cárdenas could not be reached for immediate comment. Grand jury proceedings are confidential.

A video of Marquez’s notification being read into the record was posted on Roll Call’s website.

Citing unnamed sources, the publication reported that the FBI interviewed Marquez in her home about three weeks ago, asking whether staffers in Cardenas’ office worked on campaign-related activities while being paid for official office work.

A spokesman for the U.S. Attorney’s Office in Los Angeles declined comment.