About 20 cats died in the three-alarm blaze in Passaic.
Fire Chief Patrick Trentacost tells The Record newspaper it was one of the most dangerous fires he has seen.
The chief says one firefighter was taken to the hospital for back and leg pain after he tripped and fell inside the home. Ten others sustained pulled shoulders and sore backs from throwing piles of debris out the windows.
The homeowner was taken to St. Mary's Hospital, but it's not clear why.
Officials are trying to determine what caused the fire.