MATTOON, Ill. (AP) — A 14-year-old girl has told a judge that she threatened gun violence at her school on social media.

The Mattoon Journal Gazette & (Charleston) Times Courierreports that the girl’s admission came during a hearing on Thursday. When she returns to court on April 19, a judge could order her held in a juvenile facility until she turns 21.

The Mattoon High School student posted on Snapchat last month a message to “kill you all.” The girl also called her plan “Round Two,” a reference to a shooting at the school in September in which one student was injured and another charged with aggravated battery with a firearm.

But authorities say the girl didn’t have any weapons and admitted to police that she made the threat because she was bored.