Footage shows the protests in Portland, Oregon, on Monday night (August 17).
Demonstrations sparked by the Black Lives Matter movement have continued for more than 80 days following the death of George Floyd in Minneapolis, Minnesota, on May 25.
The filmer of the video said: ''Police didn’t like the sound of passing cars honking horns in support of protestors.'' He said officers ''threw smoke bombs and shot non-lethals'' at protesters in response to the disruption.
''Protestors respond by quickly returning smoke bombs to police,'' the filmer added.