Update 3:10 p.m.:

Metro says the segment shutdowns along the Orange and Silver lines affected by this morning’s derailment will likely persist “at least through the end of the day Saturday to allow for further investigation, removal of derailed cars, and repairs to infrastructure that was damaged during the incident.” The transit agency is advising commuters west of the Ballston station to use alternate modes of transit.

The agency has not yet identified a cause for the derailment.

“Only after the railcars are moved from the scene will Metro be able to fully assess the scope of track and switch infrastructure that must be replaced,” Metro explains in a release. “In addition, Metro General Manager Paul J. Wiedefeld has directed that a third-party expert be brought to the scene to conduct a parallel, independent review of the incident and possible causes.”

Original Post:

Metro says Orange Line service between the Ballston and West Falls Church stations and Silver Line service between the Ballston and McLean stations is expected to be down for the rest of the day as the result of an early-morning train derailment.

The fourth and fifth cars of a Silver Line train carrying 75 passengers and heading to the Wiehle-Reston East stop went off the tracks around 6:15 a.m., according to the transit agency. Although Metro is investigating the derailment and has informed federal oversight agencies about it, one passenger requested medical treatment for minor injuries. The transit agency adds that the incident occurred at an interlocking area at East Falls Church, but outside a zone where SafeTrack maintenance work is being conducted through this weekend.

Customers should plan for bus shuttles, longer PM commutes through btwn Ballston, Wiehle & Vienna. Follow for updates. #wmata #EFC

— Metrorail Info (@Metrorailinfo) July 29, 2016

A Metro train also derailed last August near the Smithsonian station. While the train was not carrying passengers, Metro determined that the incident was “caused by a combination of human error and flawed processes.” Two Metro employees resigned in its wake.