According to Wikipedia a flash mob is "a large group of people who assemble suddenly in a public place perform an unusual and pointless act for a brief time, then quickly disperse."
In Philadelphia the term Flash Mob is associated with violence. On Tuesday February 16th an estimated group of 100 teens from three area high schools invaded the The Gallery an underground mall at 12th and Market Streets. Security quickly removed the group from the mall where they quickly re-gathered and a large snowball fight started along with fighting on the street corners. It's also reported that a group of 40 to 50 of the teens then invaded the Macy's store, damaging the store and carrying off large amounts of merchandise. According to the news reports, police arrested 14 high schoolers with the lone female arrestee being charged with aggravated assault. Read the story from Philadelphia.com.
This not Philadelphia's first experience with teenaged flash mob violence. In June, 2009 thousands of teens descended on Philadelphia's South Street vandalizing property, beating pedestrians and stealing a taxi.
Authorities are investigating a link between the flash mob and postings on Twitter and Facebook.
Curtis Baillie - Security Consulting Strategies, LLC