Authorities never found a gun at Orchard Knob Middle School on Monday after the discovery of several rounds of ammunition on the floor of a classroom triggered a campus lockdown.
Hamilton County Sheriff's Department spokeswoman Janice Atkinson said that in light of shootings at Coolidge Park over the weekend, officials decided to take a "proactive" approach and lock down the school while law enforcement personnel searched the property.
Several people were arrested Sunday after the Saturday night shootings left five people wounded.
Investigators still are questioning several students about the Orchard Knob incident.
"It's still under investigation as to who brought (the ammunition) and how it got to campus," said Danielle Clark, spokeswoman for the Hamilton County Department of Education.
Ms. Clark said ammunition alone is not enough to suspend a student for a zero-tolerance offense, since no weapon was found.
"Appropriate disciplinary action will be taken (against the students)," she said.
Ms. Atkinson said officials had information that a male student at Orchard Knob might have a handgun.
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