BALTIMORE (AP) — The Maryland Transportation Authority is investigating a fight on a Baltimore train after video of the melee appears to show two younger men trying to push an older man out of a moving train.

The video was posted on Facebook last week but the date of the fight is unclear.

One witness says the fight began when a young man tried to hold a train door open for his friend near the Mondawmin station, angering an older man. The video shows three men repeatedly punching each other and passengers on the train yelling. At one point, one of the younger men holds a train door open while it’s moving, and he and another young man try to push the older man out.

Police say the incident was never reported.

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