The Red Line was having a major meltdown during Wednesday morning's commute due to an apparent power problem.
The issue started just before 8 a.m., according to Metro, but no resolution was in sight as of 9:30 a.m.
At least one train was disabled and trains were single tracking in at least two spots.
Trains throughout the line have been slowed to no more than 35 mph throughout the line. The agency estimates 20-30 minute delays but riders said they were experiencing more than that.
Metro spokeswoman Caroline Lukas said the agency is still trying to figure out what happened.
Metro is encouraging riders to switch to the Green Line if possible or take a bus instead. Read below for live tweets on the problems.