The blaze broke out shortly after 9:30 p.m. in the rear attic of one of a row of 2½-story lookalike wood-frame houses packed together on Barnert Place.
The flames quickly spread to a neighboring home and then another, all within 20 minutes.
Before long, the fire was at four alarms.
Water issues hampered firefighters' efforts.
PHOTO COLLLECTION: BTFirePhotos.com
The main body of the fire was knocked down around 11:30 p.m. It was declared under control soon after.
No major injuries were reported.
City fire officials summoned members of the Passaic County Prosecutor's Arson Unit and PSE&G. The suspected cause wasn't immediately disclosed.
It was the second multiple-alarm fire of the day -- and the third in two days -- for Paterson's finest.
HEROES: Paterson Firefighters Rescue Dad, Daughter, 3, From Burning Building
Click here to follow Daily Voice Parsippany-Troy Hills and receive free news updates.