Erik Josberger was on the light rail heading to a Mariners game for a company event when he spotted a car speeding westbound down the Interstate 90 floating bridge’s bike trail.

A white car looked to be going “full freeway speed” around 1 p.m. on Thursday, the 37-year-old semiconductor research director from Renton said in an interview Tuesday morning. 

Worried “something catastrophic was going to happen,” he began to film with his phone to capture at least a license plate number. 

The car quickly outpaced the 2 Line. But about three quarters of the way toward Seattle, the train caught up with the speedster again.

The car had slowed down to a crawl, caught behind a pedestrian walking in the same direction who at first didn’t seem to notice. 

Josberger’s video, which was uploaded to Reddit, ends there. But he saw the pedestrian turn to see the car after a beat and move to the side. It was lucky the driver saw that pedestrian at all, he said, having ridden his bike along that path many times. 

Now, state officials are investigating.

Josberger called 911 right after filming. But by the time Washington State Patrol troopers got there, the car was gone, and its license plate wasn’t identifiable in the video, said Trooper Rick Johnson.

“We are hoping that witnesses call in if they have any identifying information,” Johnson wrote in an email.

The state Department of Transportation is looking into the incident, as well, to see how a car got on the car-free path.

The agency learned about the post on social media and first had to make sure it was real and not generated by AI, said RB McKeon, a spokesperson for the department: “We were pretty quickly able to determine that it was real.”

Agency officials checked out the area, McKeon said, and “there are no bollards on the Mercer Island side” of Interstate 90. Bollards are posts that are used to keep vehicles from entering prohibited areas.

For Josberger, an avid biker familiar with the path, the incident was disturbing. He is teaching his young son to bike, just having put the pedals on his balance bike over the weekend, and he wants his son to be safe on these bike trails.

The driver had made a “made a full mile of bad decisions” to get onto the bridge, he said.

McKeon called the incident an anomaly.

“The maintenance crews that I was talking to today, they don’t have any memory of something like this happening before,” McKeon said Monday.

Still, the department is concerned enough to consider measures to prevent it from happening again, she said.

The department is waiting to see what the Washington State Patrol learns about the incident and must get an understanding of who has jurisdiction over the areas where protection might be needed.

“Although we don’t want cars there, we want pedestrians, walkers, rollers,” McKeon said. “We don’t just want to swing the pendulum the other way so it can’t be used by the people for what it was designed.”