Chaos erupted at Swatch stores from New York to London as watch enthusiasts lined up for a highly anticipated new release — only for the massive crowds to force several locations to shut their doors.

The Royal Pop Collection, a collaboration between Audemars Piguet and Swatch, was released on Saturday, ranging in price from $400 to $420 a pop. But surging crowds prompted last-minute closures at multiple stores over safety concerns.

“To ensure the safety of both our customers and our staff in Swatch stores, we kindly ask you not to rush to our stores in large numbers to acquire this product,” Swatch said in a social media post Saturday. “The Royal Pop Collection will remain available for several months. In some countries, queues of more than 50 people cannot be accepted, and sales may need to be paused.”

Swatch U.S. described the launch as meeting “extraordinarily high demand,” and said at least 19 stores in the U.S. were closed Saturday “in accordance with security staff and local authorities to ensure a safe environment for everyone.” Affected locations included the Soho store in New York, the Houston Galleria, Lenox Square mall in Atlanta and the King of Prussia mall in Pennsylvania..

The company emphasized that the collection is not a limited edition.

Videos circulating on social media captured the scale of the frenzy. Footage from one video at Westfield London showed more than 50 people gathered outside a Swatch store as an announcement over a loudspeaker declared: “Unfortunately the Swatch store will remain closed for the entire day.”

In Atlanta, another video showed police blocking the entrance to Lenox Square mall while a long line of watch customers waited outside. “There are no more watches,” one officer says. “They’ll release some more. This is not a limited release.”

At the Oakbrook Center mall near Chicago, police were filmed parting the crowd to escort employees out of the store, with the entrance barricaded. According to the person who posted the video, that location had not received its shipment of the collaboration at all — a handwritten notice taped to the storefront confirmed the store would be closed for the day.