Flames shooting through the roof met firefighters when they arrived at the Levine Industries warehouse on Florida Avenue near East Railway Avenue shortly after 4:30 a.m.
The roof eventually collapsed as they worked to drown the fire from various angles, keeping it contained.
The two-alarm blaze -- which went to two alarms for manpower -- was declared under control a little over an hour later.
Levine Industries, which makes boxes and packaging materials, has operated in Paterson for more than 85 years.
It has two facilities -- a main office and packaging material warehouse on nearby Levine Street and the Florida Avenue location, where it manufactures cartons.
No injuries were reported. Authorities were investigating the cause.
Ron Bombaro took the photos. His tornadochaser66 videos can be found on YouTube.
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