Jack Persyn, 13, was in chess club before class when he discovered a short knife in the bag he brought to his Georgia school, station WXIA reports.

Persyn's aunt had bought the bag from a yard sale, and gave the purchase to the teen without checking inside first, the Atlanta-Journal Constitution reports. After Persyn told his Lanier Middle School teacher that he accidentally brought the weapon to class, the teen received four days of in-school suspension, a punishment his father Bill Persyn says is excessive.

"There was never a safety issue," Persyn told WXIA. "No harm was done. It was a genuine honest mistake, yet he got pulled out of class for four days. I can see a one-hour detention if they had to do something, but this is nonsensical."

AJC's reporter Maureen Downey contacted the Gwinnett schools, and received this statement from director of media relations Jorge Quintana:

"Gwinnett County Public Schools does not have a zero-tolerance policy. We look at situations individually and take appropriate disciplinary action. While we are not at liberty to confirm or discuss the discipline this young man faces, we know our administrators followed procedures as stated in the Student Conduct Code.

The rules call for more severe action against those students who do not self-report weapons they have in their possession. It’s important to understand that these rules are in place, in part, to prevent future incidents and rule violations. Without these rules in place, others could easily claim they were not aware of what they had in their possession."

According to a report by WFIE, the knife measured 1.5 inches long.

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