A YouTube video shows what appears to be a man hanging from the outside of a moving Red Line train traveling under the Loop.
It’s not clear when or where exactly the video was taken, but CTA officials say they are investigating.
In the video, posted Wednesday, a passenger is heard saying: “There’s this guy going crazy. He’s on the Red Line. Crazy a–.”
The dangling man appears to be wearing a white shirt and carrying a backpack on his back.
“The CTA is aware of the incident, is working to identify the individual, and will pursue appropriate charges,” the agency said in a statement. “Any reports of this kind of reckless activity are taken seriously and are fully investigated. Actions like this are extremely foolhardy and display an astonishing lack of common sense and judgment. This is not only illegal, but dangerous not just to the person involved but other passengers as well. Incidents like this can have tragic consequences for not only the individual, but for other CTA customers and employees.”