RENO, Nev. >> Thousands of people in hundreds of cars took over northern Nevada parking lots and intersections Friday night and into Saturday, performing stunts in souped-up vehicles and leading to crashes and arrests, police said.

Police beefed up nighttime staffing after social media posts urged people from San Francisco and Portland, Oregon, to come to the “sideshow” in Reno, Police Lt. Michael Browett said.

The disturbances started late Friday as several hundred cars and their occupants met in the parking lot of a still-open Walmart store. Police tried to break up the crowds and drivers sped off, meeting up again at several intersections and industrial parks into Saturday morning. A dozen people were arrested, 14 cars impounded and 33 people were issued citations.

Browett said Reno is just the latest city to see late-night takeovers by auto enthusiasts who ignore law enforcement efforts to stop the illegal and dangerous activity.

“I don’t know the underlying movement is with this group, but it goes a little beyond cars,” Browett said. “They’re very anti-authoritarian, and they basically just show up and do whatever they want.”

Cities across the country have been dealing with similar issues in recent years, including Phoenix, San Francisco and Chicago. Last weekend, three people were killed and several others badly hurt in crashes related to a pop-up sideshow in Wildwood, New Jersey.

In Reno, no one was seriously injured. But Browett said those arrested faces charges including reckless driving, hit and run causing injury and weapons possession.