School Superintendent Karen Geelan said in an email to parents Monday morning that the district was notified of the incident and arrest by the Mount Pleasant Police Department.
"Police officers reported that a resident is in custody for First Degree False Reporting an Incident," she wrote in the email. "The Westchester Assistant District Attorney is involved."
Police swept the school early Monday before students returned from the Winter Break, but nothing was found, said Lt. Robert Miliambro.
"It's business (the school) as usual and running smoothly," he added.
Officers were able to track down the 16-year-old girl after someone saw the post and reported it to their parents who reported it police, Miliambro said.
"Valhalla Schools is taking every precaution to ensure that our campuses are safe for students, staff, and visitors," Geelan wrote. "Our children should feel protected and welcomed at school."
She said parents and students should expect an increased police presence over the week. She also counseled parents to make sure they were being vigilant with their children's use of social media to prevent these types of incidents from taking place.
"To keep our community safe, online threats will be taken seriously," she added. "Our district fosters a trustworthy environment, and we need to continue cultivating a culture of attentiveness to safeguard our students."
To help educate parents about the issue, the district will host an information session, “An Evening for Children: Student Wellness, Mental Health, and Safety” on Tuesday, March 6 at 7 p.m. The district said to look for more details in the coming few days.
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