NEW YORK >> A crowd of thousands that packed Manhattan’s Union Square for a popular livestreamer’s hyped giveaway got out of hand Friday afternoon, with some clambering on vehicles, hurling chairs and throwing punches, leaving police struggling to rein in the chaos.

Aerial TV news footage showed a surging, tightly packed crowd running through the streets, scaling structures in the park and snarling traffic. Shouting teenagers swung objects at car windows, threw paint cans and set off fire extinguishers. Some people climbed on a moving vehicle, falling off as it sped away. Others pounded on or climbed atop city buses.

By 5:30 p.m., police officers in growing numbers had regained control of much of the area, but small skirmishes were still breaking out, with young people knocking over barricades and throwing bottles and even a flowerpot at officers. Police were seen wrestling people to the ground and chasing them down the street.

Police planned to charged the streamer, Kai Cenat, with multiple counts of inciting a riot, unlawful assembly and possibly other crimes, NYPD Chief of Department Jeffrey Maddrey said in the evening. Officers arrested 65 people, including 30 juveniles.

A number of people were injured, including at least four people taken away in ambulances, Maddrey said, adding that he saw other people leaving the area with bloodied heads.

“People were suffering out here,” Maddrey said. Some motorists were trapped as people climbed on top of their cars. Maddrey said several police vehicles were damaged, including his.

On his Instagram feed, Cenat had promoted a giveaway at 4 p.m. in the park. People started lining up as early as 1:30 p.m. By 3 p.m., the crowd had swelled and was getting unruly. Some young people leaving the park said they had come expecting to get a computer for livestreaming or a new PlayStation.

Skylark Jones, 19, and a friend came to see Cenat and try to get something from his giveaway. When they arrived the scene was already packed. Bottles were being thrown. There was a commotion even before Cenat appeared, they said.

“It was a movie,” Jones said. Police “came with riot shields, charging at people.”

Cenat, 21, is a video creator with 6.5 million followers on the platform Twitch, where he regularly livestreams. He also boasts 4 million subscribers on YouTube, where he posts daily life and comedy vlogs ranging from “Fake Hibachi Chef Prank!” to his most recent video, “I Rented Us Girlfriends In Japan!”

His 299 YouTube videos have amassed more than 276 million views among them. In December he was crowned streamer of the year at the 12th annual Streamy Awards. Messages sent to his publicist, management company and an email address for business inquiries were not immediately returned.

Livestreaming on Twitch from a vehicle as the event gathered steam, Cenat displayed gift cards he planned to give away. Noting the crowd and police presence, he urged, “Everybody who’s out there, make sure y’all safe. … We’re not gonna do nothin’ until it’s safe.”

Eventually he and an entourage got out of the vehicle and hustled through a crowd, crossed a street and went into the park, where Cenat was surrounded by a cheering, shoving mob.

Maddrey said Cenat at some point in the afternoon was removed “for his safety” and police were in contact with him. Videos posted on social media and taken from news helicopters showed Cenat being lifted over a fence and out of the crowd and then placed in a police vehicle.

The police chief also said a city bus filled with people who were arrested came under attack, and more police had to be sent to protect it. Numerous people were seen in hand restraints, sitting on the sidewalks, and multiple young men were taken away in handcuffs.

“We have encountered things like this before but never to this level of dangerousness,” Maddrey said. Three officers were hurt, including a sergeant who broke a hand. A teenager was injured by exploding fireworks, he said.

Businesses adjoining the square closed their doors. Carina Treile, manager of Petite Optique, an eyeglass shop nearby, sheltered inside while police dispersed the crowd.

“Usually with people giving away free stuff, it’s never like this. It’s very organized,” she said. “And here we have a very chaotic scene.”

Loud bangs at one point frightened some in the crowd.

“That was a little bit scary, especially when people started running,” Treile said.

Police, some with batons, used metal barricades to push the crowd back and loudspeakers to repeatedly declare the gathering unlawful.

“Listen, we’re not against young people having a good time, we’re not against young people gathering,” Maddrey said. “But it can’t be to this level where it’s dangerous. A lot of people got hurt today.”

Associated Press writers Brooke Lansdale, Mallika Sen, Deepti Hajela, Mallika Sen and Karen Matthews contributed to this report.