The U.S. Department of Justice is investigating a cybersecurity breach that involved the judiciary’s electronic filing and case management system, the department’s National Security Division head told the House Judiciary Committee Thursday.

The committee’s chairman, Rep. Jerry Nadler, raised the issue at the start of the hearing, noting that the U.S. Administrative Office of the Courts released a statement last January announcing extra steps the judiciary was taking to protect court records in the wake of the SolarWinds hack in 2020 carried out by Russian agents against federal agencies. The AO at the time said the court management system was likely compromised, but Nadler said the committee recently learned more about the extent of the breach.