NOTE: The video above is streaming the ABC7 Los Angeles 24x7 Streaming channel. An updated video on this story will be published soon.
The Los Angeles Police Department said a group of about 1,500 skateboarders were gathered in the 1600 block of Cherokee Avenue for an event called "Skate Jam."
There were reports of fireworks being set off and a car in flames.
It's unclear what prompted the disturbance but video from the scene obtained by Eyewitness News showed a smoldering vehicle and barriers scattered across a parking lot. The footage also showed a Los Angeles fire truck vandalized with graffiti.
Officers in riot gear were called to clear the group and remain on the scene. Police declared an unlawful assembly late Saturday night and said three people were booked for vandalism.
There were no reports of any injuries.
This is a developing story. This article will continue to be updated as more information becomes available.