Metro is warning riders to expect delays for the rest of Wednesday on the Blue and Yellow lines due to a communication line breakdown.
The transit agency said trips toward the Franconia-Springfield and Huntington stations from downtown may take 20 to 30 minutes longer because trains have to run manually at about half the usual speed along the track.
Other shorter delays may also extend to the Orange and Blue lines, the agency said.
The transit agency discovered the problem near the Braddock Road and Ronald Reagan Washington National Airport rail stations Wednesday morning in a key communication link that sends signals among the train, track and control center.
They estimate service will return to normal by Thursday morning although they warned that it repairs may not be finished until late Wednesday evening.
