It happened on an elevated platform of the 3 train near the stairs on Sutter Avenue and Rutland Rd. in Brownsville.
The 14-year-old pulled out a taser, and an 18-year-old girl stabbed her with an unknown object.
The suspect fled out of the train station with about 8-10 people. It is unclear what the dispute was about, or if the teens knew each other.
"I've lived here for 11 years and it's always something," said Brownsville resident Delecia Fraser.
As the crime scene tape went up, train service temporarily came to a halt, bringing riders like Avis Charles to a standstill.
"This is very inconvenient if you have to go somewhere," said Charles.
Others who need the train for survival are now questioning their safety.
"All these subway stations need an officer there at all times," added Gus Pompey
The 14-year-old was transported to Brookdale Hospital and is expected to survive.
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