Authorities in a New Jersey beach community triggered a night-time curfew Saturday after thousands of people swarmed the sand on the hottest day of the year.
Officials said the overwhelming size of the crowds that amassed by the afternoon threatened public safety at the Jersey Shore. Multiple fights reportedly broke out, triggering a "public safety emergency" and 9 p.m. curfew for Long Branch.
By the end of the night, police arrested 15 people, four minors and 11 adults, in connection to fights.
Thousands of young people traveled to the beach by train to attend a "pop-up party" advertised on social media, city officials said.
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Chaos reached a peak by the evening as police officers from multiple agencies responded to the beach community and attempted to control the crowds. Officers wearing helmets and carrying shields were deployed.
Tensions escalated as police used at least one flash bang and smoke "in response to fights taking place and bottles and rocks being thrown where the crowd would not disperse," the county prosecutor said.
Not long after the 9 p.m. curfew, police had the area locked down and the majority of the crowds had left the area. Countless bottles and other trash were found scattered up and down the beach in the wake of Saturday's party.
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The county prosecutor said one police car was vandalized, but no other damage or injuries were reported.
Saturday's commotion comes on the heels of last summer's beach frenzy that forced Long Branch to postpone its 4th of July fireworks show.
The curfew was scheduled to lift at 5 a.m. Sunday.