Lockdown at Cary-Grove High School

A "yellow alert" resulted in a lock down at Cary-Gove High School the day that it was named the top McHenry County high school, based on the percentage passing state tests.
The Cary-Grove High School web page announces that a Halloween prank led to the locking down of Cary-Grove High School.
Anyone with details is invited to share them in the comment section.

There were either shotgun shells or .44 magnum shell casings dropped in the halls, it has not yet been revealed formally to the student body.
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