The Pascack Road blaze broke out just before 3:30 a.m. in a first-floor apartment bathroom, leaving the second-floor residents trapped on the roof, responders said.
Firefighters attacked the flames while police grabbed a nearby ladder and got the residents down safely.
One resident sustained minor smoke inhalation, borough firefighters said. No other injuries were reported.
Colleagues from Woodcliff Lake and Hillsdale also responded, along with Tri-Boro Ambulance, Park Ridge Electric, and PSEG.
The cause of the fire was being investigated.
The Red Cross, meanwhile, was finding shelter for the residents.
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