A proposed class-action lawsuit claims Southern California surfers have spent decades using violence and intimidation to protect their surf spot from intrusion by outsiders.

The suit filed this week asks a federal judge to prevent the group of surfers known as the Lunada Bay Boys from congregating along the coast in wealthy Palos Verdes Estates, the Los Angeles Times reported.

Authorities have been accused of looking the other way as the gang threatened non-local surfers, tossed rocks at them and vandalized their cars — sometimes coordinating the attacks with walkie-talkies.

"Palos Verdes Estates has a long history of deliberate indifference in not investigating or otherwise policing acts of violence and vandalism against visiting beachgoers," the suit alleges. "The response is always the same: City leaders acknowledge the problem, promise to do something, and then do little or nothing."

The suit filed Tuesday also asks the judge to require the city to investigate and prosecute crimes committed by the Bay Boys at the popular surf break.

Police Chief Jeff Kepley and City Manager Tony Dahlerbruch did not immediately return calls seeking comment.

Kepley vowed in December to "make an example out of anyone who behaves criminally down there." He told the Times that he planned to add patrols along the coast and order overtime for officers in the city about 30 miles south of Los Angeles that's known for its multimillion-dollar homes.

"Locals only" clashes at Lunada Bay go back decades.

In 2004, an outsider attacked at the surf spot was awarded a $450,000 judgment for his injuries. A judge in the civil case ordered 24-year-old Christopher Millican to pay for the attack on Timothy Banas, who suffered a chipped tooth and injured knee.