A police officer was stabbed and at least four people were injured by a speeding U-Haul truck in events that police in Edmonton, Canada, said were being investigated as acts of terror.

One suspect was in custody, said Edmonton Police Chief Rod Knecht, adding that police believe the suspect acted alone.

The chaos began outside Commonwealth Stadium, where a Canadian Football League game was being played. Police say a white Chevy Malibu rammed a traffic-control barricade and sent an officer flying.

Knecht said the driver then got out and attacked the officer with a knife. The officer was stabbed multiple times before the suspect fled on foot, the Edmonton Journal reported.

The officer was not critically wounded, the Globe and Mail reported.

A few hours later, a U-Haul van was stopped at an impaired driving check stop and the driver sped off with police in pursuit.

Police say the U-Haul hit and injured four pedestrians before it rolled and the suspect was arrested.

“There were people flying and everything,” witness Kim Anderson told the Edmonton Journal. “I’m shocked — I just see people flying.” 

Knecht confirmed that an ISIS flag was discovered inside the van, the Edmonton Journal reported.

Later, the same suspect was pulled over at a police check stop on Wayne Gretzky Drive, this time driving the U-Haul. The suspect, believed to be 30 years old, drove off when police recognized him as the owner of the Malibu, the newspaper reported.

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