The person who saw the unnamed teenager then called the police and the school was put on lockdown before being evacuated.
All of this took place this morning at Ashwaubenon High School in Ashwaubenon, Wisconsin, a suburb of Green Bay.
Now that the dust is settled, the police are confirming that this was simply “an innocent mistake.”
According to The Hollywood Reporter, the student who arrived dressed as Darth Vader raised flags because he entered the school via the back, with the Vader mask over his face, and there was concern that the rest of the costume “looked like he might be wearing a bulletproof vest or a flak jacket.”