Canadian authorities have confirmed that a stabbing and multiple vehicle rammings near Commonwealth Stadium, Edmonton, are being investigated as terrorism.

The Edmonton Eskimos were hosting Winnipeg at the stadium for Canadian Forces Appreciation Night when a man ploughed into a police barricade in a car, Global News reports.

The driver of the car — in which an Islamic State flag was later discovered — then approached an Edmonton Police Service special duty member and stabbed him multiple times, before fleeing the scene on foot.

Roughly two hours into the manhunt which followed, a large U-Haul van was observed racing through downtown with as many as a dozen police cruisers in hot pursuit. It is reported to have struck at least four pedestrians before somehow ending up on its side.

That's what appears to be a U-Haul truck on its side at 107 Street and 100 Ave. Witness told me saw u-haul hit pedestrians. #yeg pic.twitter.com/5UszZMgCV9 — Jonny Wakefield (@jonnywakefield) October 1, 2017

One local bar manager told The Globe and Mail that he had seen the U-Haul come careening down an alleyway next to his establishment, striking two patrons.

“We were just standing out front here and basically a U-Haul was heading north down 109th Street and peeled into this smoking alley here where people were having a smoke,” he recalled.

“There was like ten cop cars following him.

“It was crazy. It just came around the corner, ripping. I thought at first he was pulling over for the cops coming by, but he was clearly the one they were chasing.”

One of the two victims was hit hard, but was assisted at the scene by a barmaid who is also a registered nurse. Witnesses say he was still breathing when paramedics came to take him away.

#BREAKING: Edmonton, Canada: Police vehicle was hit, Driver then stabbed a police officer and fled; reports ISIS flags found in the car pic.twitter.com/62C4YSR93s — Amichai Stein (@AmichaiStein1) October 1, 2017

Edmonton Police Service Chief Rod Knecht has advised the public to “be vigilant and aware of your surroundings”, but stressed that the suspect is in custody and — at this stage — is believed to have been acting alone.

“I want to be clear. We don’t believe there’s any risk to public safety right now. This is a lone individual,” he said.

Follow Jack Montgomery on Twitter: @JackBMontgomery