The Knockout Game has already showed up in a handful of cities, sometimes known by different names. In September, an attack in New Jersey left a 46-year-old Hoboken man dead of a broken neck after a group of teenagers attacked him without warning. Police said Ralph Eric Santiago was found dead, wedged between iron fence posts with a broken neck.
Several instances of the Knockout Game have shown up on YouTube.
Now police say the Knockout Game is spreading. After a series of attacks reported against Jews in Brooklyn, the game has now made its way to other cities including Pittsburgh and London.
In St. Louis, Missouri, a 23-year-old college student was punched in the face as she walked down a street. The woman suffered a double fracture on the bone underneath her left eye, CBS affiliate KMOV reported.
In Washington, D.C., a woman riding her bike was punched in the face by a teenager, leaving her with a bloody nose.
In some ways, the Knockout Game resembles another social media-fueled craze that became popular last year. Groups of teenagers would organize flash mobs in which they attacked strangers and pilfered stores. In one such attack, a group of teens stole $3,000 worth of designer jeans from a Chicago store in just minutes.
There have been reports that the Knockout Game is targeting Jews, an issue which has been addressed in New York City. In October, a community meeting between blacks and Jews in Brooklyn Heights led to a discussion about bias crimes. Police in the area said they are increasing patrols to keep a look out for the teenage attackers.