The attack occurred at 5:10 p.m. as the bus traveled on Elm Street in the Nodine Hill neighborhood of Yonkers, according to Westchester County Police.
Following the stabbing, the assailant fled through the rear door and remains at large, the department said.
The victim was transported to Jacobi Medical Center in the Bronx, where he is in stable condition, officials said.
Detectives are now working to determine whether the victim and suspect knew each other prior to the attack.
Police are asking anyone with information about the stabbing to contact the Westchester County Police Tips Line at 1-800-898-TIPS (8477). All calls will remain confidential.
This is a developing story. Check back to Daily Voice for updates.
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