One person described as a woman in her 70s was critically injured and later died at a hospital, the Oregonian reported.
Five other people were taken to hospitals with non-critical injuries, Portland Fire & Rescue said. Additional victims were not taken to a hospital, the Portland Police Bureau said during a news conference.
Witness Larry Wolfe told the newspaper he was meeting the woman for an appointment of some kind when he saw her get hit by the car. He said he walked over to her and saw the vehicle come back and hit her again before making a U-turn and leaving.
The Portland Police Bureau said it received calls around 1 p.m. about someone hit by a vehicle near Laurelhurst Park around 1 p.m., Officer Derek Carmon told reporters. As officers were responding to the hit-and-run, they received more calls about the same vehicle hitting other people and vehicles.
Authorities did not confirm how many cars were struck. Police said there were multiple crime scenes.
The suspect, who was not identified, eventually crashed the vehicle and fled on foot, police said. He was held by several community members until police arrived.
Another witness, Cody Warnes told the paper a heavily dented Honda Element turned into oncoming traffic and hit a cyclist.
A motive has not been determined.