Forsyth County District Attorney Jim O'Neill announced Monday that a grand jury had indicted the 17-year-old, who was arrested last week. She now faces three counts of murder and one count of conspiracy.
"The thought of her going back to school, with the weekend approaching, holy days approaching, we didn't know what she was capable of," O'Neill said at a news conference.
Authorities say the attack was carried out by two males — aged 17 and 18 — who opened fire on the Islamic Center of San Diego before taking their own lives. The district attorney said the gunmen had two objectives: "Number one, to kill as many people as possible on that day. Secondly, they wanted this carnage and destruction recorded ... livestreamed."
Under North Carolina law, a person charged with aiding and abetting a crime can be held criminally responsible in the same way as the person who carried it out, O'Neill explained.