McMinnville and Warren County, Tenn., law enforcement officers were posted at every Warren County school Thursday morning in response to a threat that was posted on Facebook on Wednesday night.

In the post, the person threatened gun violence at a school, officials said. News of the threat quickly spread throughout the county and many parents kept their children at home Thursday.

Director of Schools Bobby Cox said those students will not have the absence counted against them.

Cox said school officials were confident that students would be safe today with the extra law enforcement on hand. Principals were instructed to restrict who could enter the doors and be in the hallways. Some schools chose to go under lockdown conditions, officials said.

Meanwhile, state and local authorities are investigating the threat, trying to determine who posted it. Officials are not sure if the person is local or out of state.