The fire broke out on the sixth floor of the building at 1560 Grand Concourse.
Authorities say the three-alarm fire broke out inside apartment 603 just before 7:25 p.m. and spread to two other apartments and through the roof.
The women were pronounced dead at nearby BronxCare Health System, the former Bronx Lebanon Hospital.
All the women were older, longtime residents of the building, officials said.
A fifth woman was injured.
Terrible night as our community lost four neighbors. Unbelievably sad. Our district mourns the loss of our residents and prays for the families! 🙏🙏 4 women killed in 3-alarm Grand Concourse, Bronx apartment fire: NYPD | https://t.co/aL5t9MmgUw https://t.co/ceeJ144QS0— Vanessa L. Gibson, MPA (@Vanessalgibson) April 1, 2020
Fire officials have determined a space heater in apartment on the sixth floor caused the fire.
The Red Cross is providing assistance to displaced residents.
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