Around 1:15 am on July 9, a vehicle drove into downtown Portland, where dozens of protesters had congregated, and the driver fired several shots into the air, the Portland Police Bureau said Thursday.

According to police, the driver attempted to turn heading the wrong way on Southwest Main Street. Protesters began engaging with the driver—a common response during protests to direct drivers away so they don't injure anyone in the crowd.

Video captured at the scene shows protesters urging the driver of the white car to get out of the road. The driver then sped away and fired at least four shots into the air in quick succession. Nobody was injured.

The investigation is still active. Police said they couldn't locate the driver and blamed demonstrators for inhibiting officers from searching the area for evidence of the shooting—by standing in the crime scene.

"Officers in the area attempted to locate the vehicle but were unsuccessful," PPB said in a news release. "Due to the demonstration, officers were unable to canvass the area for evidence until later. No evidence was recovered from the scene."