Rosebud-Lott ISD is conducted a thorough search of the entire school district on Thursday after receiving an unidentified written threat.
In a statement, officials said Rosebud-Lott High School was made aware of a note in a boy's bathroom that prompted a "shelter in place order."
The Falls County Sheriff Department, Lott Police Department and Rosebud Police Department were notified immediately.
Parents were notified via the parent notification process.
The McLennan County Sheriff's department provided a dog trained to find possible threats and proceeded to search lockers, backpacks, closets and vehicles.
Administrators and law enforcement will continue to investigate the source of the threat.
Rosebud community members said the threat came as shock, given the town is so small.
"Something that happened this close to home...it's rattling," said Saul Resendis, who has two younger siblings enrolled at the high school.
He said he didn't believe the notification sent out by the school at first.
"You see it on the news, you see it on the TV, on movies and stuff but you never think it's gonna be here," he said.
Clara Pirkle, who owns a shop on Main Street in Rosebud, said she hopes the threat was just a prank of some sort.
"Just pray for him. That's my first thought. To pray for somebody because they're evidently in a kind of frustrated state," Pirkle said.
The district intends to have school as planned on Friday but will not allow backpacks at school.
Additionally, students may be subjected to searches if the administration deems necessary.