Metro says Red Line trains will be returning to automatic mode. It's a significant milestone for the agency, which has run trains in manual mode since the 2009 train crash that killed nine people.
Starting today, eight car trains will run in automatic mode. That means trains will accelerate, decelerate and stop under computer control, making for a smoother ride.
Train operators will be in the cab of each train to open and close doors and make announcements. Metro says six-car trains on the Red Line will operate in manual mode until after a software upgrade later.
The 2009 Metro crash was caused when the automated system failed. Metro's five other rail lines are expected to return to automatic train operation in late 2017.
The Associated Press contributed to this report.