The footage, filmed on a Manhattan subway, sees Danay Howard, 21, teasing 21-year-old Kevin Gil about his dress sense, while both their friends look on.
When a bystander films the incident, the woman smacks the phone out of his hand.
However when she responds to Gil branding her a 'bitch' by shoving him with her handbag, the New Yorker slaps her to the floor in a violent outburst.
While the woman's friends jump to her aid, they are overpowered by Gil's male friends, who can be seen beating them up.
Even more shockingly, barely any of the cowardly bystanders -including the passenger who is filming- jump in to break it up, with just two men getting involved.
But the upsetting video has divided opinions, with some viewers claiming the confrontational women 'deserved' the mens' reaction.
However others argue that while restraining someone is acceptable, the men are clearly bigger and stronger than their female counterparts, and are able to do much more damage with a simple slap.
Howard, Gil, and two others have been arrested over the incident.
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