Police said protesters in Portland, Ore., chased a truck before it crashed and then assaulted the driver late Sunday.
The incident occurred around 10:30 p.m., police said in a statement on Monday, as protests in Portland stretched on for the 80th consecutive night.
Portland police said officers responded to a report of an injury accident, adding that protesters chased the truck before it crashed and assaulted the driver afterward.
The driver was transported to the hospital by ambulance with serious injuries, police said.
Officers encountered a hostile crowd and a squad from the rapid response team responded to help secure the scene, according to the police department, which added that an investigation is underway and no arrests have been made.
Video footage shared on social media shows a group of people kicking, punching and pushing a man to the ground after his truck crashed into a light pole at Southwest Broadway and Taylor Street, Oregon Live reported. Another video on Twitter cited by the outlet shows the man bleeding from the back of the head.
Earlier in the night, protesters gathered for a peaceful rally and speeches around Chapman Square and Lownsdale Square parks, police said.
Portland police declared a riot on Saturday evening after officers and police vehicles were allegedly hit with rocks and other objects.