Police have charged a Carter County teenager in connection with an online threat that sent several local schools into a lockdown last month.

Carter County Sheriff Dexter Lunceford said investigators with his department have charged a 15-year-old female with one count of felony false reporting in connection with the investigation into the threats. He stated the juvenile is a student at Happy Valley High School, one of the schools specifically named in the threat.

“Through the investigation, we determined that the young lady who made the original report to the principal was actually the suspect in the case,” Lunceford said on Wednesday.

On Feb. 28, several Carter County and Elizabethton City Schools went into a lockdown around lunchtime after police discovered a threat to local schools on social media. Lunceford said at that time a specific threat had been made against Cloudland, Happy Valley, and Elizabethton High schools on the popular social media app “After School.” The app allows students within a specific geographic area to connect with each other.

The post on the social media app said at 12:30 p.m. on Feb. 28 an armed subject would go to each of the three named schools and begin shooting, Lunceford said.

Lunceford said his department was made aware of the threat around 11:30 a.m. The Sheriff’s Office and the Elizabethton Police Department investigated the threat and gave the schools the clearance to lift the lockdown around 1:10 p.m.

Officers found no evidence of a legitimate threat at any of the schools on the day the incident happened, Lunceford told the Elizabethton Star on Feb. 28, adding that his investigators were already in the process of tracking down the individual who originally posted the threat on the social media app at that time.