The fire started around 11 p.m., Saturday, Dec. 25 at 81 Elliott Ave., in Yonkers.
Arriving firefighters found a full fire from the bottom of the building to the roof of the four-story unit, said Yonkers Fire Commissioner Anthony Pagano.
All Yonkers firefighters responded to the fire that could have easily destroyed the entire block, the commissioner said.
Three other nearby units were damaged with smoke and water, displacing a total of 11 families, including at least seven children.
The more than 12 firefighters injured suffered from smoke inhalation, sprains, and other injuries, he added.
All of the families were able to escape without injury.
"The department did a great job containing the fire to the one unit with such a tremendous volume of fire," Pagano said.
Due to the size of the fire, the fire department was on the scene for more than 18 hours.
The Red Cross is assisting displaced families.
The cause of the fire is under investigation.
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