On Aug. 31, 1986, Huntington Beach descended into chaos.

A crowd of roughly 100,000 people had gathered for the annual Op Pro surf competition. The trouble started, reports said, after some men tried to rip the bathing suits off of two young women behind the bleachers. When officers came to the women’s aid, they were met by a barrage of beer bottles.

“They could have killed us if they wanted to,” a Huntington Beach officer recalled later in the L.A. Times.

Surfers watched from the water, dumbstruck, as the crowd on shore morphed into a full-scale riot.

Shirtless young men in flip-flops ransacked a lifeguard building. They tore apart hand rails and used the metal rods to shatter police car windows, then flipped the vehicles over and set them on fire. Black smoke filled the air.

After roughly an hour of destruction, police in riot gear arrived and restored order. All told, at least 12 people were injured, including six law enforcement officers. Dozens were arrested.

In the aftermath, there were calls to end the contest, which is part of a world tour. A tour executive suggested maybe Huntington Beach was just too susceptible to lawlessness. The event ultimately continued, but with some changes imposed by the city: Alcohol was banned. So were bikini contests. The date was moved from Labor Day weekend to early August.

Still, the surf contest has continued now and then to teeter toward disorder. Another rampage, albeit much smaller than the 1986 riot, broke out in 2013 — prompting a new round of soul-searching and even tighter rules.

Watch video from the 1986 riot:  YouTube

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