The teen was stabbed three times, in the torso and extremities, at Yonkers Middle High School on Rockland Avenue.
He was taken to Westchester Medical Center and was said to be stable and undergoing surgery.
Two 17-year-old students were taken into custody after the incident and a knife was recovered. Police anticipate they will be charged with felony assault.
Police say a fight started between the teens in a bathroom and spilled out into a hallway on the second floor of the high school. They say the older two students punched and kicked the younger student and then one of the 17-year-olds stabbed the victim.
School security immediately responded and stopped the fight.
The incident was captured on cellphone video and surveillance cameras inside the school.
"It was kind of chaotic. Everybody was like, 'what's happening? What's going on?' Then we were on lockdown for a little bit. So we really weren't able to go out of the classrooms and people were scared," student Isabella Caminero said.
A statement from school officials said there was no threat to public safety and the school resumed normal operations by 9 a.m.
They said pupil support professionals will be available to assist students or staff and there will be additional district staff at the school throughout the day.
For some parents, there was no hesitation in racing to pick up their kids after the incident.
"That's something that should never happen. As a parent, my daughter's 16 years old, so you don't think that you're sending your kid that morning to school and you're going to get a phone call that they're in the hospital or that they've been injured in any type of way by another student," parent Emmy Caminero said.
The investigation is ongoing.
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