A young woman and her infant were killed when a fire ripped through their Mount Vernon home early Sunday, officials said.

The blaze started on the second floor and quickly spread to other parts of the Westchester County home around 3:30 a.m., authorities said.

Nine of the home’s 11 residents escaped the blaze and told firefighters that Nina Bryant, 30, was still in the home with her 7-month-old daughter, Nadia.

It took firefighters more than an hour to beat back the flames enough to reach the second floor, where they found the woman and child’s burned bodies, officials said.

The cause of the fire is still under investigation.