OTTAWA: A motorist in Canada's Edmonton city rammed into a policeman and then attacked him with a knife on Saturday night while a van driver went on to hit four pedestrians in a pair of suspected terror attacks, reports said.

Canadian police say they are investigating possible acts of terrorism after multiple incidents in the capital city of Alberta province, reported the BBC.

According to police, a police officer controlling traffic at a Canadian Football League game was struck by a car at high speed and then attacked with a knife by the driver who then fled abandoning the vehicle. Shortly afterwards, a van driver rammed into four pedestrians at least.

This driver was chased and arrested by police.

Police said that an Islamic State flag was found in the vehicle.

While the policeman did not have any life-threatening injuries, the condition of the pedestrians was not known, said the BBC, citing police.