A day after hundreds of Metro riders ended up stuck underground in Southeast Washington, authorities were still trying to piece together how the evening rush hour on the Green Line turned into such a dangerous mess.

Dozens of the stranded passengers opted to climb out out of the trains and into the tunnels, according to officials, in a risky reprise of a botched train evacuation last summer.

Riders reported panicked and uncomfortable scenes on the stuck trains and little information on what was going on or how long it would last.

Once the trains made it to the stations, there was crowding and confusion. At Navy Yard/Ballpark, Anacostia and other Metro stops, passengers were frustrated by the absence of shuttle buses and lack of official direction.

Metro General Manager Richard Sarles apologized publicly to riders Thursday and promised a thorough review.

Metro's Green Line service disruption

In a statement, he said, “there is more that can and will be done to better assist our customers during such incidents. The responsibility for improvement rests squarely on our shoulders at Metro.”

In an interview with The Washington Post, he said that what happened was “unacceptable to customers and unacceptable to me.”

During Thursday’s evening commute, Sarles went to the Navy Yard station and greeted customers, saying it was “good to hear unfiltered comments” from commuters. “There were some who were very unhappy, and I don’t blame them,” he said at the station.

The statements, the interviews and the visit to the Navy Yard station were part of an unusually aggressive public-relations response by Metro, which is in the midst of a campaign to build support for major improvements to the aging transit system.

This is just the latest in a string of problems for Metro’s operations. Dozens of riders were stranded Sunday night for two hours on an Orange Line train that lost power near the Cheverly station. And on a sweltering July day, about 150 riders fled a stalled Green Line train near College Park after it lost power and air conditioning.

Several months ago, The Post filed a request for reports and other materials related to July’s incident on the Green Line, but the transit agency has not released the information.

Sarles said Thursday that the transit agency has begun an investigation into the most recent incident and that the results will be presented next month to a committee of board members. The final report will be made public, Metro officials said.

The problems began about 4:40 p.m. Wednesday when Metro crews responded to a smoking piece of the third rail outside the Anacostia station.

As a result, trains had to share a single track between Navy Yard and Southern Avenue, which caused delays and crowding for Green Line riders as the evening rush hour was getting underway.

A slow, inconvenient commute became a potentially dangerous one just after 5:30 p.m., when the power was cut in the tunnel between Navy Yard and Anacostia with two trains still on the tracks.

Sarles said a Metro employee “hit the emergency power down button” — which killed power to another segment of the track — because the employee “perceived it was a safety issue.”

Metro officials said the employee was authorized to shut down the power. They would not identify the worker.

After power was cut, Metro “didn’t follow protocols entirely, and as a result it took longer to figure out what was going on and recover,” Sarles said.

With no power, two Green Line trains, each loaded with riders bound for Anacostia and beyond, were stranded while waiting for their turn to approach Anacostia.

Between 100 and 200 passengers on the train farther from Anacostia began exiting at 5:59 p.m., according to Metro. They climbed onto the track bed, and Metro cut the power. Emergency personnel had to get riders out of the tunnel through a vent shaft that leads to Anacostia Park.

Darlene Cunningham, who was on one of the trains, described an increasingly tense and uncomfortable scene while waiting for help.

“We were in the middle of the tunnel, and the train just stopped,” said Cunningham, 40, a senior at Howard University studying audio production. “The lights went off, and that was it.”

A child near her began crying, while others wondered aloud if they were going to die. One elderly woman fainted, Cunningham said.

Riders repeatedly pressed the call button to reach the operator, who initially was responsive and told people about the power being shut off. After about 10 or 15 minutes, the operator stopped answering, Cunningham said.

After about an hour, she said, emergency responders showed up and began leading the passengers through each car to the front and off of the train into the tunnel. From there, they were guided to the Anacostia station platform and allowed to exit without paying.

Confusion continued once riders reached the platform. Riders had been told there was a fire at Anacostia, so they didn’t know if they should stay on the platform or head into the station, according to Cunningham. The situation worsened when they emerged to the “chaotic scene” outside.

“Metro officials weren’t telling us what to do or where to go,” she said.

Ted Froats, who was at Navy Yard, described a similar scene.

“The most frustrating part was the lack of communication for riders and between Metro employees,” he said. “No one seemed to know what was going on.”

Mort Downey, the head of the Metro board’s safety and security committee, said Thursday that he was concerned that people went into the tunnel on their own.

“It is not something that should happen,” he said.

The Tri-State Oversight Committee said it is “monitoring the progress of [Metro’s] investigation” of Wednesday’s incident. Lon Walls, a D.C. fire department spokesman, said his agency is also investigating what happened and why.

Three people were taken to a hospital; one was in serious condition.

One of the new procedures that Metro implemented after the College Park incident was to get more of its personnel on the scene and to speed communication with riders, Sarles said.

During Wednesday’s incident, Sarles said that Metro personnel were on the scene within 15 minutes of the power going down and that police were on the stranded trains in “under 30 minutes.”

Clarence Williams contributed to this report.