SACRAMENTO (CBS13) – A sideshow stopped traffic on Business 80 near Cal Expo Sunday afternoon.

California Highway Patrol says four cars stopped on the southbound side of the freeway and started doing donuts. Officers soon showed up and the cars left.

Still from a video of the sideshow sent in by a CBS13 viewer.

Still from a video of the sideshow sent in by a CBS13 viewer.

One car was impounded and the driver got a ticket, CHP says.

Witnesses say the sideshow blocked traffic for about 30 minutes.

Sideshows are illegal events where drivers perform stunts with their vehicles, sometimes shutting down roadways or freeways. A sideshow in Stockton ended violently recently after suspects pelted officers with rocks, causing significant damage to a couple of patrol cars.