Two Metro trains ran through red signals in the past month, leading to safety retraining in the transit agency.
Both incidents occurred in Washington's Brentwood Rail Yard near the Rhode Island Avenue station, WTOP reported. The incidents happened April 20 and May 6.
Running a red signal is like a car running through a red light. It can lead to a collision. Last year a Red Line train derailed intentionally to avoid a crash after it ran through a red signal near the Farragut North station.
Both train operators acknowledged their violations and are being retrained, Metro said. Such incidents are rare.
The signal in question is unusual, assistant safety officer Ken Sundberg said. It's on the left side but most are on the right.