The blaze broke out in Ulster County around 12:50 p.m., Monday, Jan. 31, at 109 Rondout Drive in Kingston.
When Kingston firefighters arrived on the scene located at the Roundout Gardens Apartments, they found heavy fire coming from a second-floor apartment, extending to the attic, said the Kingston Fire Department.
When the fire started, the mother and her newborn were able to escape without injuries due to a smoke detector, the department said.
"She was able to safely remove herself and her newborn without injury due in part to her quick thinking and the smoke detector being operable and alerting her," the department said on Facebook.
A second alarm was transmitted and firefighters performed a search of the involved apartment and stretched a hand line to extinguish the fire.
A third alarm was transmitted and other arriving firefighters evacuated adjoining apartments.
A mutual aid FAST team from the Stone Ridge Fire Department responded to the scene.
Shortly after 1 p.m., the fire was contained and crews began checking for any hidden fire.
In total, Kingston had 17 firefighters on scene with an additional 15 firefighters manning other apparatus to cover future calls for service.
Esopus Fire and Port Ewen Fire also responded for stand-by coverage.
There were no injuries, the department said.
The occupants of the apartment are being assisted by the Red Cross for temporary housing.
The fire was investigated by the Kingston Fire Investigation Unit and determined to be accidental and still under investigation.
Also assisting on the scene were the Kingston Police Department and Central Hudson Gas and Electric.
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