There are more than 300 of them in New York — violent crews of 12- to 20-year-olds with names such as Very Crispy Gangsters, True Money Gang and Cash Bama Bullies.
Police say they're clustered around a particular block or housing project and are responsible for about 40 percent of the city's shootings.
They say most of that violence stems from the smallest of slights: Dirty looks on the street, or disses on Facebook and Twitter.
Experts say the trend of smaller, younger crews has emerged as police have cracked down on bigger, more traditional gangs.
In 2012, the NYPD initiated Operation Crew Cut, focusing on gathering intelligence about specific crews through traditional street policing, trolling social media sites and by monitoring jailhouse calls.
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