Heidelberg University says police also found a blow dart gun and brass knuckles in Monday's search.
Police say 18-year-old David Conrad, of Westlake, has been charged with aggravated menacing and possession of marijuana paraphernalia. Other charges are being reviewed.
There are no court records indicating whether Conrad has an attorney, and a call to his home wasn't answered Tuesday.
The university says Conrad has been suspended and won't be allowed back on campus. It says school policy prohibits weapons on school property without written permission.
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