(Photo by John Sonderman)

Metro announced today that it is opening up a criminal investigation into the East Falls Church derailment, after information uncovered during an administrative review of the incident “raises potentially serious concerns,” said General Manager Paul Wiedefeld in a statement.

On July 29, two Silver Line train cars derailed at the East Falls Church station with 75 passengers on board.

A preliminary investigation from Metro found that rail ties near the East Falls Church station had deteriorated, causing the rails to be too far apart, though “car equipment, weather, temperature and other factors remain under review.” The agency’s yearlong maintenance plan SafeTrack had not addressed that part of the tracks at the time of the derailment.

The Safety Department’s administrative review, which is ongoing, “uncovered information that warrants further investigation by Metro Transit Police,” Wiedefeld said. “While Safety Department investigations determine cause and accountability, it is even more important to understand if other issues must be addressed with the way track inspections and maintenance have been conducted.”

Metro’s general counsel has retained the services of two former assistant U.S. attorneys—Adam Hoffinger and Peter White—to support the internal administrative review.

“The information uncovered to date raises potentially serious concerns, and we will take all actions necessary to get answers and hold people accountable,” Wiedefeld said. The agency has not commented on what, precisely, this uncovered information is.

According to the release, the parallel investigation through Metro Police comes after “investigators advised [Wiedefeld] of concerns arising from employee interviews, inspection reports, rail defect tracking, and video recordings.”

Wiedefeld wanted to assure riders that multiple internal and external groups are charged with quality control over the SafeTrack work, and Metro is additionally having an outside firm review its track inspection program.

The National Transportation Safety Board issued a report citing “ineffective inspection and maintenance practices” for the death of Carol Glover, a 61-year-old grandmother who died during the smoke incident that occurred near L’Enfant Plaza in January 2015.