Two dozen officers and dog units swarmed McMinn County High School for a surprise search on Thursday.
The sheriff held a quick briefing prior to the mission at the school. Officers then moved on to the scheduled lockdown. Students were kept inside the classrooms while deputies moved through the school.
Their goal was to find contraband, and they did find a few pocket knives, tobacco, lighters, and a small amount of marijuana.
Authorities did give students a chance to admit they had something in their locker or their car that is forbidden on school grounds.
"If they do that and take advantage of that amnesty opportunity, we don't charge anyone. Of course they will be counseled by school administrators about making better decisions, but that's about as far as we'll go," said Sheriff Joe Guy.
The sheriff's office runs a handful of these spot checks every year at schools in McMinn County.