Police are investigating after a video on social media showed a section of Highway 409 illegally shut down Saturday night as onlookers cheered a driver doing doughnuts on the road.

A video of a car revving and spinning in circles went viral after it was posted over the weekend on the popular Instagram page @6ixbuzztv, popular enough that it caught the attention of Sgt. Kerry Schmidt of the Ontario Provincial Police.

“This is not only dangerous and illegal, it is disappointing when a mob mentality of hijacking a highway to make a scene like this is conducted,” he wrote after reposting the video on Twitter. “We are better than this ... aren’t we?”

More than a dozen onlookers, many recording, are seen in the video. The stunt held up traffic behind them in the area around Carlingview Drive and Pearson International Airport. Schmidt said those involved fled after Toronto police and the OPP arrived. Callers estimated that about a hundred cars were held up as a result, he said.

The Instagram page has since been set to private.

“It’s certainly concerning,” Schmidt told the Star. “The participants themselves could have lost control and hit someone, hit a wall, or another vehicle, or other motorists coming from behind, not realizing the highway is shut down.”

He says they’ve been receiving videos from drivers stuck as the stunt went on and participants since the Instagram post went viral. No suspects have been arrested.