Protesters briefly blocked northbound lanes of the 405 Freeway at Wilshire Boulevard in Los Angeles Monday afternoon.
Cars could be seen backed up behind the protest, with some taking the shoulder of the freeway to pass them.
California Highway Patrol officers could be seen blocking the protesters from on-coming traffic.
After a not a longtime, protesters exited the freeway and continued toward Westwood.
Hundreds of people marched through downtown Los Angeles in a Black Lives Matter protest over the death of George Floyd in Minnesota.
The march resulted in a violent confrontation with police, including the smashing of CHP cruiser windows, and the shutting down of the 101 Freeway near downtown.
An estimated 500 to 1,000 people participated in the event, starting near City Hall and then marching through downtown.
It appears the event was not cleared with city officials in advance as there was a minimal police presence in the area.
At one point, dozens of protesters wandered onto part of the 101 Freeway near downtown and surrounded a CHP cruiser.
The cruiser tried to escape the crowd and someone damaged the back window with a skateboard.
As the CHP car tried to flee, a man rode on the car's hood for a few seconds, then fell off and appeared to hit his head as he fell to the ground. He then remained motionless as a crowd gathered around him.
A second CHP vehicle tried to assist and was also surrounded and had its window damaged. That vehicle also left.
Authorities were later able to get the crowds off the freeway.
Crowds were blocking downtown streets in the area of Temple and Los Angeles streets as they carried signs and stood still in the intersection.
he marches was a reaction to the death of Floyd and video showing an officer placing his knee of Floyd's neck while he was handcuffed on the ground.
Los Angeles Mayor Eric Garcetti sent several tweets in response to Floyd's death and the local demonstration.
"George Floyd was killed before our eyes - and we have every reason to be angry, to cry out for justice, to say never again," he wrote.