The NYPD says an off-duty MTA subway cleaner was stabbed on the 5 train platform in Pelham Bay.
Police say the incident occurred just after 6 a.m. Thursday morning.
Police said an argument began between a rider and the 47-year-old worker.
Officials said when the argument quickly escalated, the rider stabbed the worker in the armpit.
The MTA worker was transported to NYC Health + Hospitals/Jacobi and is in stable condition.
The suspect remains on the run. Police described the suspect as a man between the ages of 55 and 60, with a dark complexion and a beard. They said he was last seen wearing a dark hoodie and dark pants.
Anyone with information on the incident is asked to call the Crime Stoppers hotline at 1(800)577-TIPS.