What began as a group robbery ended in a homicide aboard a subway train. Prosecutors have provided a rare look into the district attorney’s decision not to charge a man in the fatal stabbing, saying surveillance video shows the victim acted in self-defense.

Jennira Roundtree, 43, was knifed in the heart and lungs and slashed with an umbrella outside Staten Island’s West Brighton Houses.

A 43-year-old mom was stabbed to death outside her Staten Island building while defending her daughter during a large brawl this week, according to law enforcement sources. Jennira Roundtree was knifed multiple times in the chest around 7:30 p.

A 43-year-old woman was fatally stabbed near her Staten Island home on Tuesday evening, authorities said. At around 7:35 p.m., police responded to a 911 call of an assault near the West Brighton Houses apartment complex located at 820 Henderson Ave.