Some groups of teenagers in Harlem use the messaging website Twitter, via their mobile phones, to organize street fights and other shady activities.

Manhattan’s young thugs have turned to Twitter, and the cops who track them are fast behind, the Daily News has learned. Investigators are monitoring the traffic in hopes of sweeping up gangbangers before the bloodshed - and searching Twitter after attacks for clues.
“It is another tool … just like old phone records,” a police source said. “We can go through them [messages] to track these guys.”

Read more in: NYDailynews November 29