The attack happened on a northbound train just after 11:15 p.m. Wednesday.
The 39-year-old victim was stabbed in the chest and slashed in the right arm in the unprovoked attack. The victim got off at the 191st Street station and went to Harlem Hospital, where he was stable.
The stabber, who stayed on the train, is described as a man in his 30s, wearing a red hat and a black shirt, and carrying a red duffle bag. He was recognized by police and MTA workers as a frequent rider of the No. 1 line who has harassed riders in the past.
One rider said while he isn't concerned about his own safety, he doesn't like to see people in his community get hurt.
"I don't worry about my safety, I've lived here for 45 years. I'm not worried," the rider said. "It bothers me. I'm not pleased about violence happening to anyone, especially in my community. My prayers are with the young man and his family."
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