LOS ANGELES (CBSLA.com) — Nine teenagers have been charged with robbing pedestrians during a so-called “bash mob” in Hollywood last week, according to the Los Angeles County district attorney’s office.

Three girls and two boys, all 16, and four 15-year-old boys, whose names are being withheld, pleaded not guilty to the July 16 rampage at Hollywood Boulevard and Highland Avenue. They’re expected to return to court in August.

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The young adults are accused of taking people’s cell phones, a wallet and a skateboard.

Police believe the “bash mob” was sparked by messages on social media.

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