Orange Line riders are facing delays Monday due to an early morning signal problem followed by two separate disabled trains in northern Virginia and the District.

The most recent wave of delays is the result of a disabled train near the Metro Center station just before 8 a.m. Metro said trains on the Orange and Blue lines are single-tracking between Smithsonian and Farragut West.

An hour earlier, around 7 a.m., Metro said that trains were single-tracking between West Falls Church and Vienna stations, with delays in both directions, due to a disabled train at the Dunn Loring station.

This problem added to residual delays from an earlier signal problem at West Falls Church.