Police say the victims, two men and one woman, were slashed at the Sutphin Boulevard/Archer Avenue station just before 9 a.m.
The incident apparently began as a dispute on a J train that continued when they exited. The attack happened on the escalator heading up to the street level.
The victims, identified as 24-year-old Princess Llsop, 34-year-old Antoine Roddy and 42-year-old Andres Nova, were rushed to Jamaica Hospital for treatment of non-life threatening injuries.
Authorities sayLlsop and Roddy are a couple and were the people involved in the dispute with the suspect, 25-year-old Dina Saint-Fleur. Nova was a bystander on the escalator who fell during the commotion. It was unclear if he was slashed at all.
Saint-Fleur, who may be emotionally disturbed, was taken into custody.
E and J subway trains were bypassing the Sutphin/Archer station in both directions due to the police investigation.
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