A 12-year-old was facing juvenile charges after authorities said he fired a gun inside a bathroom at his suburban Chicago middle school.
Police said the 9 mm gun may have been accidentally fired into a toilet at MacArthur Middle School in Berkeley on Tuesday afternoon.
Police Chief Dale Gustafson said authorities believe the boy tucked the loaded gun into his waistband and had it with him for the entire school day.
Superintendent Eva Smith said in a statement that the boy never threatened anyone with the weapon. When administrators asked him why he had the gun, he said: "I don't know." It's not clear where he got the weapon.
He was being held in the Cook County juvenile detention center.
Berkeley is about 14 miles west of downtown Chicago.