Large gatherings of young people spur concern around the country about "teen takeovers." That refers to events organized on group chats, TikTok, Snapchat and Instagram that draw crowds -- sometimes reaching the hundreds -- to downtowns, parks, beaches and malls. Amplified music, traffic blockages and vehicle stunts bring police responses. Fights have erupted, as have a few shootings, though not all social media meetups devolve into violence.

Sites of the phenomenon this summer include Washington, D.C., St. Louis, Detroit, Chicago and Houston. In Orlando, Fla., hundreds of teens on e-bikes blocked downtown traffic last month. The July 4 holiday weekend was marred by rowdy youth crowds in Buffalo, N.Y., Newport Beach, Calif.; Pensacola, Fla., and Raleigh, N.C.

Detroit imposed an 8 p.m. curfew for those under 18 on the night of a downtown fireworks display in late June and assigned more police to parks and recreation centers this summer. After 12 minors were arrested during a July takeover in Charlotte, N.C., that city is considering a 9 p.m. curfew for anyone under 18. "I am very concerned that if we don't get a handle on this, the consequences may become fatal," Police Chief Estella Patterson told council members two weeks ago.

Some city officials and urban scholars see the disruptions as evidence of the need for places where teens can hang out, barbecue, play music, dance and party safely. Chicago Mayor Brandon Johnson says he condemns violence, but feel it's "not constructive to demonize youth who have otherwise been starved of opportunities in their own communities." Detroit Mayor Mary Sheffield extended recreation center hours to 11 p.m. this summer, resumed a late-night basketball program and started free youth-focused events with DJs and gaming trucks. "Our young people need more than just enforcement," the first-term mayor says.

Law enforcer says: "It's all organized through social media. Instead of one person telling another person, now one person's telling hundreds of people." -- Deputy Police Chief Michael Walek of Clearwater, Fla.

Scholar says: "Teens are desperate for human interaction and social contact. And when there's a chance to gather and be part of something larger, we see teens flock to it." – Samuel Abrams, senior fellow at the American Enterprise Institute in Washington, D.C.

Federal prosecutor says: "Teen takeovers have disrupted neighborhoods, forced businesses to close temporarily and diverted valuable law enforcement resources." – Jeanine Pirro, U.S. attorney for the District of Columbia