It happened on a northbound 2 train at 149th Street and 3rd Avenue just before 3:30 p.m. Saturday. Police say the two men got into a verbal dispute and took out a knife and stabbed the other man in the chest.
The 33-year-old victim was taken to Lincoln Hospital in extremely critical condition and was later pronounced dead.
The 36-year-old suspect was taken into custody.
Ali Hoeite was trapped on the same 2 train on Saturday afternoon with other frightened passengers as the two men fought.
Hoeite says the man who ended up dying was stabbed with his own knife by the other man.
"He took the knife from him, and boom, he push it in the heart," he said.
The deadly stabbing forced the 149th Street-Third Avenue Station to close for a police investigation.
It is a station that always seems to be at the center of trouble, Isma says.
"That is why sometimes I don't want to ride the subway - I want to take the bus. But even on the weekend - a lot of problems. It's very scary," Isma said.
It is unclear if the two men knew each other.
The investigation is ongoing.
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