The 13-count indictment against Michael Brandon Hill was filed Thursday in DeKalb County Superior Court. The charges against Hill include aggravated assault, terroristic threats, firearms violations and obstruction.
Circuit Public Defender Claudia Saari, whose office is representing Hill, said she had no comment Friday. The office earlier said Hill has "a long history of mental health issues."
Police have said Hill went to Ronald E. McNair Discovery Learning Academy in Decatur with an assault rifle and nearly 500 rounds of ammunition. Although no one was injured, police have said Hill exchanged gunfire with officers.
A school bookkeeper was credited with calmly persuading Hill to surrender.
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