Juan Rivera, 18, was found with a handgun, drugs, and drug paraphernalia inside his bookbag at West Chester East High School around 9:30 a.m., West Goshen police said.
There were no reported injuries, according to police.
Rivera was charged with firearms not to be carried without a license, possession with intent to deliver, possession of drug paraphernalia, possession of a controlled substance, and possession of a weapon on school property.
He was released from custody Friday after posting 10 percent of $50,000 bail, according to court records.
His preliminary hearing is set for Feb. 2, records show.
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