Police say the 17-year-old male student slashed a 53-year-old aide in the left arm with what authorities believe was a scalpel just after 10 a.m.
A 30-year-old man, also a teacher aide, attempted to intervene and suffered a minor cut to the hand.
Both were taken to BronxCare Health with minor injuries.
The suspect fled the scene. He was last seen carrying a blue backpack and wearing a black shirt and blue sweater.
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