When Damarion Spann, 18, saw an Instagram flier calling for a massive gathering on a beach near downtown Chicago, he immediately wanted to go. Thousands of others joined him that night on the sand, blasting music and dancing.

The cultural trend of so-called teen takeovers has popped up across the U.S. in recent years, influencing local policing and national politics. The events, often hyped online and captured in videos on social media, have led to shootings, theft and vandalism. City officials and police are concerned about an increase over the summer, and are under pressure to prevent similar gatherings or to punish those who participate.

The Associated Press

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