David Cornelius described what he saw earlier this week as so dangerous, he thought the man doing it was a stunt man.
A video that surfaced in Channelview, Texas, shows a man rolling in and out from under a moving train, eventually scampering over to the other side, narrowly missing the fast-moving wheels.
"That's crazy," Cornelius told KHOU-TV. "I ain't ever seen anything like that."
Brad Rayford, who also saw the man rolling around under the train, told the news station he's seen him do it before, noting that "it almost hit his legs."
Watch video of the man's dangerous stunt in KHOU's report:
Union Pacific, the railroad company running these tracks, told KHOU that this man's actions are illegal and could harm himself and others if he continues.
"This is never a game," Union Pacific spokesman Jeff Degraff said, according to the news station. "You're taking your life and the lives of others in your hands."
If caught, this man could be fined, KHOU reported.