Police were investigating a cellphone video showing a man dragged off a Metro train in Long Beach.
The incident happened at the at the Metro Blue Line's Wardlow Station on Wednesday at 10:30 p.m.
An officer assigned to the Metro Blue Line responded to help firefighters with a medical call.
The case came to light after cellphone video surfaced showing a rider in a suit dragging a man off a train.
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The video showed the man half naked and unconscious being dragged on his back onto the train platform.
Passengers can be seen trying to wake the man up by clapping loudly in his face.
Detectives from the Long Beach Police Department's Violent Crimes Detail are reviewing the video to determine if a crime occurred.
"Obviously, this is very disturbing and we never want to see this on our system," Metro officials said in a statement. "We're getting all the facts, including reviewing the video from the train and the platform, and we'll share more details when they're available.
Metro officials say that if someone is in distress, we encourage people to call 9-1-1 for medical assistance. If you have more information about the incident, please call Metro security staff at (888) 950-SAFE.