British riots exposing social media's dark side?

As the riots in England set parts of the country burning, authorities say social media is fanning the flames, CBS News correspondent Randall Pinkston reports.

The rioting began after Mark Duggan was shot and killed by police. A memorial Facebook page quickly went up, and, 15 minutes later, there was this post:

"Please upload any pictures or video's you may have from tonight in Tottenham. Share it with people to send the message out as to why this has blown into a riot."

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It was a call to arms that has now erupted for four days. As rioters and looters took to the streets, instant messages typed on BlackBerrys began to fly among them, in effect organizing the chaos.

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"Everyone from all sides of London meet up at the heart of London (central) Oxford Circus!!" one reads.

"Bare shops are gonna get smashed up so come get some (free stuff!!!)" another reads.

It's a dark side to social media, which was praised last spring for its role in fueling the popular uprisings in Egypt and across the Middle East.

(Earlier this year, CBS' "60 Minutes" broadcast a report on the protests in Tunisia that ousted a repressive government and spread to other nations.)

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"Generically speaking, the Arab spring and the London summer are identical," said Wired.com's John Abell. "You have disenfranchised youth using tools of the trade, things they carry in their pocket, and spontaneously erupting into one thing or another."

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By contrast, after riots erupted in Vancouver, Canada, following the Canucks' Stanley Cup loss in June, a reporter for CBS News' Seattle affiliate told "The Early Show" that he found a Facebook page dedicated to organizing people to clean up the city's damaged downtown area.

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Americans typically think of flash mobs as something unsuspecting and entertaining like groups suddenly breaking out in song or busting out dance moves in bathing suits.

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But, increasingly, Internet-organized mobs have turned ugly. A flash mob -- or flash rob as it has come to be known -- organized a group to rob a Sears store just outside Philadelphia in June.

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Social media can even be unintentionally disruptive. A recent incident in which a Los Angeles disc jockey attempted to organize a party turned ugly when police were called in to break it up.

"Technology is amoral," said Abell. "It's agnostic to its use. It's the use that people put to it that is at issue."