(ISLA VISTA, Calif.) -- Hundreds of law enforcement officers worked to calm the crowds at the annual "Deltopia" party in Isla Vista, Calif. Saturday.
The block party, attended by thousands, turned violent as people threw rocks, bricks, and bottles.
Dozens of people were hurt, including police officers. One officer was hit in the head with a brick while another officer needed hand surgery after being struck with a bottle.
Authorities used tear gas, pepper spray, and rubber bullets to try to control the crowd. Police say more than 50 people were arrested.
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