DARBY, Pa. (CBS) — The discovery of a gun inside of a school in Delaware County prompted a lockdown on Thursday, officials say.

William Penn School District Superintendent Jane Harbert says there was a fight Wednesday that happened off campus, but it was brought into Penn Wood Middle School today.

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Darby Police were called to the scene once the gun was found.

Authorities searched the school and an arrest was made.

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There were no reported injuries and the school is back to normal operating order.

Officials say security will be ramped up during school dismissal.

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