Edmonton Police chief Rod Knecht said that officers took a suspect in custody and they think he acted alone.
Late on Saturday, a auto crashed into a police barricade near Commonwealth Stadium in Edmonton, after which the driver approached a policeman and stabbed him several times.
Thirty-year-old Abdulahi Sharif has been charged after a police officer was stabbed and four pedestrians were struck down by a fleeing U-Haul truck on Saturday night.
Police officer attacked with vehicle and knife while pedestrians targeted in high-speed chase in western city of Edmonton. While checking the driver's license, the officer recognized the name as being similar to the registered owner of the Chevrolet Malibu. The U-Haul then sped off toward Jasper Avenue, downtown Edmonton's main east-west thoroughfare, with multiple police cars in pursuit.
The incident in Edmonton shows that terrorists can strike anywhere and use improvised weapons to carry out #terror attacks, injure innocent people and terrorize the masses. The suspect then jumped out of the auto, stabbed him and fled the scene, police said.
"The Government of Canada and Canadians stand with the people of Edmonton after the terrorist attack on Saturday", Canadian prime minister Justin Trudeau said on Sunday."We can not - and will not - let violent extremism take root in our communities", he added. "We continue to collect and gather information related to this investigation ... if additional charges are supported, they will be pursued at that time".
Police have detained a suspect accused of ramming his vehicle into a police officer before stabbing him and fleeing on foot.
The CBC reported Mr. Sharif worked on a construction crew at one point, and quoted an unnamed former colleague saying Mr. Sharif was sympathetic to the Islamic State, prone to religious rants about "polytheists" and expressed "genocidal beliefs".
The terrorist threat level stays at medium, where it has been since late 2014.
The van "peeled" into an alley where people were smoking, he said.
Knecht said the apparent ISIS flag would be "part of the investigation", adding that there had been no prior warning of a specific attack. "Edmonton is a strong and resilient city, and I am confident that its citizens will support one another to overcome this tragic event", the prime minister said.
"We can not - and will not - let violent extremism take root in our communities".
The vehicle later flipped on its side and the suspect was arrested.
Police chased down the attacker as he drove through the packed out streets in downtown Edmonton.
"There were like 10 cop cars following him".
"The complexities of a terrorism investigation are vast", she said.
Alberta premier Rachel Notley last night tweeted to wish the injured officer a "speedy recovery". It was insane. It just came around the corner, ripping.