More than 2,900 Warren County, Tenn., students missed school Thursday while local law enforcement agencies swept into every campus in the county after a threat of violence against the school system was posted on Facebook.
On Wednesday evening, someone went on a memorial page set up for a local student who died in October and threatened gun violence at Warren County High School, said Director of Schools Bobby Cox.
"We put in place a plan to have a high presence of law enforcement today," said Cox. "Anytime we get a threat, we're going to take it seriously."
Law enforcement officers with the McMinnville police, Warren County Sheriff's Office and the Tennessee Highway Patrol took up posts at the 11 schools in Warren County's system.
Cox said the school system recently had revisited and tightened its crisis management plan.
Other security measures Thursday included having principals restrict who could enter the schools.
It is still unclear who posted the threat, or why. Cox said state and local officials are investigating and that the name used in Friday's post appears to be a false identity.
"Instruction has pretty much been nonexistent today, which is very sad," said Cox. "But it's worth it, making sure everybody is safe. It's sad that it kept kids home from school when they should be learning and having the best days of their lives."
Cox said law enforcement officials once again will be posted in every Warren County School this morning as a precaution.
McMinnville, the seat of Warren County, is about 70 miles northwest of Chattanooga.