It happened at a 16-story building on Riverdale Avenue around 9:15 a.m.
The fire destroyed several balconies and forced residents to evacuate the building.
Officials believe the fire started on a balcony or near one on the sixth floor and then jumped floors via the balconies.
The flames spread to a few units with windows open. In all, about 10 to 12 units out of 240 were impacted by the fire.
No injuries were reported, but a shelter has been set up for residents while authorities assess which apartments are safe to return to.
"As soon as you went into the staircase, you could tell your breath was being taken away because of how much smoke there was," building resident Chanel Guzman said. "It was so dry, and then as you got down more down to the ground level, it was just more smoke."
The fire reached five alarms before it was brought under control, meaning every fire company in the city of Yonkers was on the scene battling the blaze.
The exact cause of the fire is under investigation.
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