WASHINGTON (AP) — Metro officials are apologizing for an incident that left hundreds of passengers stranded for hours on Metro’s green line Wednesday evening.

Some panicked after the power went out on two trains waiting underground in southeast Washington. Dozens of passengers from one train evacuated themselves, walking onto the track bed.

Metro General Manager Richard Sarles apologized publicly on Thursday. He says Metro must do better to help customers during such incidents. He says Wednesday’s mess was unacceptable.

Metro has said it’s dangerous for passengers to evacuate without assistance because some tracks may be electrified.

There have been several similar incidents. On Sunday, night, an orange line train stranded dozens of passengers for two hours near the Cheverly station. And in July, about 150 passengers fled a stranded train near College Park.

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