LACKAWANNA, N.Y. (AP) — A 20-year-old student at an alternative school near Buffalo faces charges after bringing a gun inside the school in his backpack.

Authorities say the weapon set off the metal detector at the Baker Hall School in Lackawanna Monday morning.

The finding led school officials to place the building on lockdown for most the day. Lackawanna police charged the student with possession of a loaded firearm and possession on school grounds.

School officials say they don't believe there was any threat to other students.

According to its website, the private school enrolls students from ages 11 to 21 who have been diagnosed with an emotional disturbance, intellectual disability, multiple disabilities or a traumatic brain injury.

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