Police Sgt. Darin Ryburn tells City News Service that the teen was taken into custody late Tuesday after authorities received several calls.
Ryburn says the threat indicated a desire to harm a fellow student at John Burroughs High, and referenced past national school shootings.
Police interviewed the intended victim and suspect, and arrested the 16-year-old boy.
Ryburn says it appears to be an isolated incident, and all involved individuals have been identified and interviewed.