The incident occurred at about 3:30 p.m. Thursday. The school nurse told officers that the boy had shown up in the office holding his bleeding hand, police said.
He had apparently severed part of his thumb after getting it caught in a bathroom door, police said. The nurse dressed the wound and applied pressure while EMS workers responded, police said.
The boy's parents were notified, and he was taken to the hospital, police said.
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