Huntington Beach police Lt. Mitchell O'Brien said Monday that one person was treated for injuries at a hospital after apparently being hit by a bottle and a rubber projectile police fired to disperse the crowd on Sunday night.
O'Brien says some officers also suffered minor injuries.
Police say more than 100 officers were called in to quell the violence that erupted when a fight followed the surfing contest.
O'Brien says the raucous crowd tore out a street sign, toppled portable toilets and broke windows.
Police say nine people were detained and two were later released.