(CNN) A Somali refugee charged with five counts of attempted murder is accused of stabbing a police officer in Edmonton, Canada, after hitting him with a car and later plowing a truck into pedestrians on a busy street, injuring four.
Abdulahi Hasan Sharif, 30, also faces charges of dangerous driving, criminal flight causing bodily harm, and possession of a weapon for a dangerous purpose, Royal Canadian Mounted Police (RCMP) Superintendent Stacey Talbot said at a press conference Monday.
While authorities were investigating the incidents as acts of terrorism, no terrorism charges have been filed against Sharif at this time.
"The complexities of a terrorism investigation are vast ... if additional charges are supported, they will be pursued at that time," Talbot said.
Sharif, who police believe acted alone, is expected to appear in court Tuesday morning. CNN's attempts to reach an attorney representing Sharif have been unsuccessful.
The suspect was investigated in 2015 after police received a complaint he was "espousing extremist ideology," said RCMP Deputy Criminal Operations Officer Marlin Degrand, but there was insufficient evidence to pursue terrorism charges. He was not deemed to be a threat at the time, Degrand said.
The first incident happened Saturday at 8:15 p.m. (10:15 p.m. ET) when police say the driver of a white Chevrolet Malibu purposely struck an officer directing traffic. Police had set up the roadblock near Commonwealth Stadium for an Edmonton Eskimos football game.
The driver jumped out of the vehicle and attacked and stabbed the officer several times with a knife and fled on foot, said Chief Rod Knecht of the Edmonton Police Service. There was an ISIS flag in the car, which has been seized as evidence, the police chief said.
Knecht said Officer Mike Chernyk, who was thrown 15 feet, had severe abrasions on his arms and suffered stab wounds to his face and head, but will make a full recovery.
After that incident, police broadcast the name of the Chevrolet's registered owner to patrol officers in the city.
Just before midnight, a police officer stopped a U-Haul truck at a checkpoint and recognized the driver's name as similar to that of the Chevrolet's registered owner. The truck then sped off toward downtown Edmonton with police chasing it.
The U-Haul traveled on busy Jasper Avenue, which late Saturday night and early Sunday morning was full of football fans and bargoers, reported CNN partner CBC. During the chase, the truck deliberately attempted to hit pedestrians in crosswalks and alleys in two areas along Jasper Avenue, Knecht said.
At least four pedestrians were injured. By Monday morning, two had been released from the hospital. At least one remains in serious condition, Talbot said.
As police gave chase, Knecht said, there was no indication the suspect would stop.
"As a result, a deliberate tactical maneuver by a police vehicle was authorized and successfully executed, causing the suspect vehicle to roll onto its side," Knecht said.
Officers broke the truck's windshield and used a stun grenade on the suspect before attempting to remove him. When he refused, they used a Taser on him and arrested him, Knecht said.
"No shots were fired," Knecht said. "In fact, no shots were fired anywhere in this entire incident."
Prime Minister Justin Trudeau said his fellow citizens were in solidarity with the people of Edmonton.
"We cannot -- and will not -- let violent extremism take root in our communities," Trudeau said. "We know that Canada's strength comes from our diversity, and we will not be cowed by those who seek to divide us or promote fear."