A pair of reckless thrill-seekers filmed themselves riding on the outside of a Los Angeles Metro train for about 21 minutes as it traveled beneath the city.
An Instagram video of the daredevil duo shows one of the riders perched on the front of a moving D Line train while another records from just behind as they cruise ride through subway tunnels and several underground stations.
The footage shows the train speeding through tunnels as lights and other infrastructure flash by just feet away.
At several stops, passengers can be seen waiting on station platforms before the train pulls away again with the pair still riding on the outside.
The video continues for the length of the journey before ending at the Mid-Wilshire station, where both of the riders climb down from the front of the train and walk away.
It’s unclear when the video was filmed or if there were other individual involved.
One commenter who claimed to be a train operator offered a dire warning to the daredevils.
“As a Train Operator, this is absolutely reckless,” the commenter wrote on the clip. “One wrong move, and they can fall off, get thrown into the third rail and fried from the inside out, or fall, where they can’t recover, and get chopped in half by the following train.”
The clip is the latest example of a dangerous social media trend where young people film themselves riding on the outside of moving trains or subway cars for online attention, despite the obvious risk.
The practice, also known as “subway surfing,” has repeatedly drawn warnings from transit agencies across the country, which have cautioned that the stunt can result in serious injury or death.
