A student at Crosby High School in Waterbury was arrested after a firearm was found in his book bag, according to Waterbury police.
Police said officers responded to the high school at 9:30 a.m. after receiving a report that a student had a gun at school and they found a .22 caliber firearm.
School officials said police responded immediately when the administration was made aware of the weapon. No information was immediately released on what the weapon was.
Crosby High School and Wallace Middle School were put into a shelter-in-place, which has since been lifted.
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An 18-year-old student has been charged with criminal possession of a pistol or revolver, possession of a weapon on school grounds, carrying a pistol without a permit, theft of firearm, risk of injury to a minor and breach of peace in the second degree.
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