Police were called to the Evan G. Shortlidge School on 18th Street Thursday morning.
Action News was on the scene as a woman was led away by police.
The school's assistant superintendent told Action News that the woman was upset because of an incident at her child's bus stop.
While the school's doors are kept locked, the woman was allowed in because she is a recognized parent.
However, once inside, the woman started acting 'irate' and 'out of character,' the school official said.
That's when the principal spotted something on her person that looked like a weapon, leading to the initial police dispatch of a person with a gun.
Officers on the scene then said they believed she had nunchucks. However, at this point, it is unclear what the item was on the woman.
Officers remain on the scene as this investigation continues.
The school was on lockdown for about an hour, but that lockdown has since been lifted.