At the start of the school day, police were called to Eddystone Elementary School, where they confiscated the BB gun and identified the student accused of bringing it in, Eddystone police said.
Police said the unidentified student was "charged accordingly," but did not specify those charges.
No injuries were reported.
"This incident is a serious matter, and we will continue working hand and hand with school officials for maximum safety," police said in a Facebook statement.
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