Philadelphia train passengers pin down alleged gunman until police arrive: Video

A group of Philadelphian train passengers held down an alleged gunman after a Thursday shooting incident until police arrived, video shows.

A 19-year-old was shot in his left arm on a Southeastern Pennsylvania Transportation Authority (SEPTA) train just before 8 a.m. The incident spilled onto the 52nd Street Station platform in West Philadelphia, with a few people detaining the suspected shooter before police arrived.

Cellphone footage captured by witness Mark Krull shows Market-Frankford Line passengers holding the suspect down until police arrived on the scene.

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“Keep the kids down, keep the kids down,” one man is heard saying in the video.

“It looked like they were beating somebody up. You hear a muffled gun shot and we all ran out of the train and hid behind one of those blue storage things SEPTA has,” Krull told FOX 29 Philadelphia. “I was a bit shaken up. I ride the train all the time and it’s usually not violent.”

The victim is in stable condition. Police said that the shooting started with an argument between two male passengers.

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“That altercation was quickly joined by two additional males, erupting into a full-blown three to one assault,” Acting Chief Chuck Lawson said.

Authorities said that three men were taken into custody, with a fourth suspect still sought by police.

Fox News Digital reached out to the Philadelphia Police Department for a statement, but no new details are available.