A social media video showing a person riding on the top of a speeding GO Train has spurred a full investigation by Metrolinx.

The video surfaced on social media over the weekend but it’s unclear when exactly it was recorded.

In the 10-second clip, the thrill-seeker in question pans the camera to show a 360 degree video of the top of the train.

Though the person’s face is not visible, the video briefly shows their feet dangling off the edge of a car and later planted on the train, which suggest they're standing.

“As soon as I saw it I gasped,” Metrolinx spokesperson Anne Marie Aikins told CTV News Toronto.

“I thought, ‘How on earth is anyone staying on top of a train going that fast?’”

The double-decker trains are an estimated 24 feet high and at full speed, can go 80 km/h, Aikins said.

She said it was likely the train was moving that fast.

“These trains, they’re very, very high and they go very, very fast. That suction from a heavy, heavy train like that going fast would throw anyone off,” she said.

“He’s having a great deal of difficulty keeping his balance, which is not surprising, and then it ends. So we don’t know the end result of that video.”

The transit agency’s safety officers are now investigating the video and trying to determine the person’s identity.

Aikins said there are “a number of violations” that could be involved in a stunt of this kind.

GO riders commuting in the GTA on Monday were shocked to see the level of danger the unidentified person put themselves in.

“I think it’s a little crazy to be honest,” said one rider. “A lot of people just do stuff for internet points.”

“He’s literally on a moving train,” another shocked rider said. “If something happens, he could fall off and die.”

This isn’t the first time that people have been caught pulling stunts on moving transit vehicles.

Back in February, a video surfaced of a young man filming himself riding on the back of a TTC subway train. And in 2016, another young man was hit with a $425 fine after he filmed a satirical video, in which he walked onto TTC subway tracks.

With files from CTV News Toronto's Tracy Tong.