Portland police are seeking witnesses to a collision at Southwest 4th Avenue and  Madison Street on Saturday, in which the driver of a silver Lexus slowly pushed through a crowd of protesters crossing the street.

Video of the incident obtained by WW's news partner KATU-TV shows the car turning right into a crosswalk while the "walk" sign signaled that pedestrians could legally be in the crosswalk. A man dressed in black stops, plants his feet and places his hands on the hood of the Lexus. The driver continues to gently press the gas, slowly moving the man down the street several feet as other people bang on the car's windows.

Portland police say the driver of the Lexus contacted the bureau and reported his vehicle suffered $3,000 in damage. The video shows protesters hit the exterior and photos show a cracked driver's side window.

Police say they are seeking witness statements from the pedestrians to "learn what occurred from their perspective."

A spokesman for the bureau says officers may forward evidence to the Multnomah County District Attorney's Office without additional witnesses, but having the pedestrians' statements might strengthen a case against the driver prosecutors decide to bring one.

"The information provided by those individuals is important and it would be optimal to provide the information to the MCDA for their review," says spokesman Sgt. Christopher Burley. "It is important to note that the video may leave questions that cannot be answered without a person being present to answer the questions."