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The same technologies that for years have brought together the mostly benign and goofy "flash mobs," in which groups suddenly break into dance at a mall or stumble around like zombies at train stations, is being used to plan and execute bold robberies.

Called “flash robs,” these crimes are being organized by young teenagers through various social media outlets, most notably Twitter. Police say the suspects select a time and place and enter the store in droves taking what they want and leaving before security or police can catch them.

Some of the most brazen robberies take place in the light of day and on busy streets despite all the security cameras and the watchful eyes of workers.

“Young people are risk takers; they do things in groups far more than adults do. A medium like Twitter plays into the characteristics of young person’s behavior,” Scott Decker, a professor of criminology at Arizona State University, told FoxNews.com.

Because of these flash plots, police have begun to more closely monitor social media sites, reports the Chicago Sun Times.

The pack mentality emboldens the thieves to strike fast, so fast that the store clerks don’t have time to react.

“Over 90 percent of crimes committed by young people are done so in a group,” Decker told FoxNews.com

Technology hasn’t just made it easy to plan and organize. It’s allowed the thieves to off-load their loot. A recent survey done by a leading retail industry group shows that technology has led to a spike in organized crime, mostly as thieves find it easier to sell stolen goods online.

Of 129 retailers surveyed by the National Retail Federation, nearly 95 percent said they were victimized by organized criminals in the past year and 85 percent said the problem has worsened over the past three years.

But Decker says these tech-savvy criminals could be in it for something more -- the fame. Seeing themselves on the security videos of the robberies that are uploaded on YouTube or shown on the nightly news can be a thrill to teenagers, he said.

“It’s a way of bragging,” Decker said. “Not only can you show your friends, you can show the whole world. “

Their brazen moves are matched by their high-profile targets.

Chicago's Magnificent Mile has been targeted numerous times; Filene's Basement, The North Face and Express have all been robbed by these flash mobs, reports the Sun Times.

These arrests and the rise of mob robberies in Chicago has prompted Police Chief Garry McCarthy vow to crack down on these robbing teens. “We can’t tolerate this stuff. ... We’re not going to let it go,” he told the Chicago Sun-Times.

Here’s a look at some of the most recent robberies.

Chicago

Last week, four violent assaults and robberies occurred in Chicago’s upscale area of Streeterville. One man was dragged into the street and beaten by a group of 15 to 20 teenage males after a baseball was thrown so hard at his head that his motor-scooter helmet was knocked off. Another man was robbed of his cell phone and camera after being knocked off his bike and punched by a group of teenage males. Three teenagers were recently arrested due to their alleged involvement with these strings of flash mob robberies, four of which occurred within a 10-minute span.

And on June 9, Jesse Andersen, the 35-year-old brother of Smashing Pumpkins frontman Billy Corgan, was punched in the face as his iPad and money were stolen by multiple perpetrators.

Washington, D.C.

On April 25, G Star Raw, workers at a retail store in Dupont Circle were caught off guard as a group of about 20 teenagers swarmed the store, stopping to look through sizes, taking over $20,000 worth of merchandise and promptly exiting the building. Store Manager Gregory Lennon told FoxNews.com that their staff has a heightened sense of awareness of customers who enter their store in large groups, but there is little they can do to protect themselves from another flab mob attack. D.C. was previously hit two weeks prior, when a store owner of a small T-shirt shop was pushed out of the way as she tried to protect her store from the 20 to 25 teenagers who robbed it.

Flash Mob Robberies Not A Rare Occurrence in DC: MyFoxDC.com

Las Vegas

In May, 20 teens were caught on camera as they robbed a convenience store and stole about $600 worth of merchandise and the clerk's cellphone. They were in and out in a matter of minutes. "It became a feeding frenzy," store owner Jon Athney told KLAS-TV. "They were in the store for three minutes and 30 seconds. ... It's a pretty scary thing."

Many of the employees of these stores were temporarily paralyzed by the scene, making this form of teenage robbery very effective. It's “tremendously anxiety-provoking and fear-provoking when a large group of people engage in a criminal act,” Fox News contributor Dr. Keith Ablow said. The workers likely were in shock, because “It takes time to realize what is going on.” The robbery was caught on tape and police are still investigating the crime.

St Paul, Minn.

On Feb, 19, 50 teenagers swarmed a busy convenient store causing confusion and panic among the store’s employees. They stole anything they could get their hands on, food, candy, soda, juice. Although police are not sure if the two events are related, shots were heard a few miles away from the robbed store, and two young people were rushed to the hospital with gunshot wounds. This is not the first time this has happened in St. Paul. A BP station was robbed by 20 teenagers four months prior. The clerk was assaulted, and the assailants fled the building in different directions.

St. Paul Stores Suffer ‘Mob Thefts’: MyFoxTWINCITIES.com