The problems began at 1:30 p.m. with what Metro called an "arcing insulator" issue. A train operator reported that it started on the track between Dupont Circle and Woodley Park-Zoo/Adams Morgan, moving in the direction of Shady Grove.
Emergency personnel used an extinguisher to solve the problem, although they did not exactly cite a "fire" as the issue.
A track circuit problem at the Farragut North Metro stop also contributed to the delays. Normal service resumed around 2:50 p.m.