The event was promoted by Kai Cenat, best known for his livestreams on the gaming site Twitch and YouTube videos. He had earlier announced a “huge giveaway” on his Instagram account for 4pm.

Before the event began, footage from news choppers showed people flinging bottles and chairs, climbing onto the roof of a subway entrance, tearing down construction barriers, standing on top of cars and unloading a fire extinguisher.

Video from TV news helicopters showed Cenat in a black SUV, standing with his head through the moon roof, as people mobbed the vehicle. At least one person fell off the car as it drove away from the scene.

It was not immediately clear what had sparked the chaos.

By 5pm, police had set up barricades around the square and largely contained the crowd.

A spokesman for the city police department said no injuries had been reported as of 4.45pm and that there was no information yet on the number of arrests.

In a social media advisory, the department urged people to avoid the park, which is near New York University.

Cenat, 21, has 6.5 million followers on Twitch and 4 million subscribers on YouTube. He was named “Streamer of the Year” in 2022 at the Streamy Awards.