, May 19 -- The launch of a new Swatch model triggered chaotic scenes in several cities around the world, highlighting the growing influence of "drop culture," where limited-edition products attract huge crowds and are quickly resold at much higher prices.

In Paris, police used tear gas to control crowds. In Milan, a fight broke out. Long overnight queues were seen outside Swatch stores in London, Singapore and New York City.

At the center of the frenzy is the Royal Pop, a colorful pocket watch developed in collaboration with luxury Swiss brand Audemars Piguet.

The watch sells for about $400, but many buyers were hoping to resell it online for thousands of dollars. Listings quickly appeared on eBay, with some asking more than $4,000. ...