In this file photo, commuters make their way to and from trains at Gallery Place Metro station in Washington, D.C. (Salwan Georges/The Washington Post)

Fireworks ignited on a Green Line train at Gallery Place Metro station Wednesday night caused panicked passengers to flee and dozens of police to swarm the station platforms, authorities and witnesses said Thursday.

Metro said a firework went off on a 7000-series train shortly before 9:30 p.m. The trains had its doors open at the time — and riders, some of whom thought they heard gunshots, dived under an escalator structure and crammed into other areas for safety.

“It was pandemonium in the station,” said David Poland, 66, of Rockville, who was arriving back in the region Wednesday night after a trip to visit friends in Mexico City. “It was scary as hell.”

The transit agency said no one was injured, and officers determined the cause was one or more fireworks about 90 seconds after arriving at the scene, Metro spokesman Dan Stessel said. The agency was reviewing surveillance footage from the train on Thursday as they sought the culprit.

Poland said he had gotten off the Yellow Line and was preparing to transfer to the Red Line upstairs when “we just heard bam! bam! bam! bam! bam!” Passengers left shoes and bags behind on the platform and ran, he said. Some dove into a train that had pulled up to the platform, he said.

“Everybody was scared and running,” said Poland, who was with his 21-year-old son when they took cover under the concrete escalator structure.

“There was a fair bit of stuff left on the platform. People just dropped it and ran,” he said. “And then it just stopped.”

A short while later, after things had calmed down, the two took the escalator up to the Red Line and saw police with guns drawn on the platform.

“It took about a minute,” Poland said. “They actually responded quite quickly.”

Metro said multiple officers were already inside the station at the time of the incident. A suspect had not been identified Thursday.

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