WINCHESTER, Va. (DC News Now) — A 16-year-old Millbrook High School student was behind bars after making violent threats on social media.

Frederick County, Virginia school administrators discovered the threats on social media last Friday and notified the sheriff’s office. The student was taken into custody and admitted to having a plan to commit “acts of violence.” The sheriff’s office said the investigation was still in the “beginning stages.”

“We detained him and interviewed him and brought a parent in,” said Lt. Warren Gosnell with the sheriff’s office. “Based upon that interview, he admitted to posting these messages onto social media. One post included a photo of a firearm, a handgun.”

The student faces federal charges and has yet to formally enter a plea in court.