ANNA (CBSDFW.COM) — A 13-year-old will spend the night and possibly the weekend behind bars. Police say he sent several friends a photo of himself with a gun telling them not to come to school the next day.

The boy’s release depends in part on when he can see a judge. If they can’t schedule a detention hearing Saturday, it could be Monday at the earliest. Meanwhile, a lot of parents of students at Anna Middle School are furious about how they found out about it all.

By the time Alexia Swanepoel got an automated message from the school district, she says it was too little, too late.

“Hello, this is Anna Middle School. We understand that a news station had a news story about an Anna Middle School student being arrested,” a voice on the robocall could be heard saying.

Swanepoel says she had long since sent her kids to school. Then long before the robocall, she read on Facebook that a 13-year-old boy was charged Thursday night with making a terroristic threat. Police say the eight grader admitted to posting a photo of himself with a gun and a warning for his friends to stay away from school.

“I would have thought that the school district would have called us early this morning. Like about 6:00, 6:30 because I would have wanted to talk to my children first before they would have even arrived to campus,” Swanepoel said.

The automated message from the school district went on to say that the incident did not happen on school property and no children were at risk, but Bobby Davis says that’s not the point.

“I feel like the school took away my right as a parent to make the decision of whether or not to send my child to school today,” Davis said.

The district’s superintendent didn’t want to appear on camera, but he tells us he chose not to inform parents because he didn’t want to create panic, and he didn’t realize the media would report the incident so quickly.

“I think that the school district has a responsibility to us as parents to let us make those decisions,” Swanepoel said.

Police tell us the boy remains charged with one count of terroristic threatening. That’s a Class B misdemeanor. The school superintendent says this student has no history of disciplinary problems, so if the charges don’t change, he will likely be able to return to school.

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