The girl sent a message from an anonymous Instagram account to the student saying she was going to "kill all of you and your Egyptian friends," after altercations between Black and Egyptian students last week, NJ Advance Media reports citing district officials.
The investigation is active, however, did not appear to be a bias incident, city spokeswoman Kimberly Wallace-Scalcione said.
The teen was charged with false public alarm and two counts of terroristic threats. It was not clear if she was a student.
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