Chicago Police officers, including some working undercover, have been stationed at Chicago Transit Authority stations to stop "flash mobs" before they form.
The response is to the flash mobs and wildings that one alderman acknowledged are "giving our city a real bad name."
Groups of youth are using text messaging and social media to gather at specified locations as so-called "flash mobs" primarily on the city's South Side, where robbers attack people with pepper spray. Of late, flash mob attacks were reported in the Streeterville neighborhood.
Flash-mob violence has also been reported in Los Angeles, Philadelphia and Washington D.C.
Source: Chicago Sun-Times
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