Racial slurs and death threats were left on the answering machine at the Cobb County NAACP.
Marietta Police say it was a 13-year-old who left the message, telling the staff it was his job to murder black people. He also used the n-word and referred to himself as Johnny Rebel.
This wraps up a two week investigation conducted by the FBI.
The caller's voice may have been disguised with a computer program or mobile app to make his age less obvious. His age prevents police from releasing his name or photograph, and the documents that would shed light on why the boy made the call are also unavailable.
Police say he will be charged in juvenile court with terroristic threats.
Copyright 2018 Meredith Corporation (WGCL-TV) All rights reserved.