Four people in all were hospitalized in the Market Street fire, all with injuries that weren’t considered life-threatening, firefighters said.
A total of 18 people were displaced, they said.
Arriving units said they found heavy fire in the basement shortly after 9 p.m.
They raised a bucket ladder to a third-floor window to rescue the three trapped occupants, getting them all down safely and securely, the Perth Amboy Fire Department said. They were then turned over to EMS for transport to an area hospital.
Meanwhile, other crews entered the building.
They withdrew temporarily as the first floor partially collapsed, then returned inside once it was deemed safe, the department said.
Flames extended to the second floor before firefighters finally had the blaze knocked down.
City relocation officers and the Red Cross assisted the displaced residents, who were taken to the nearby Jankowski Center.
Among the departments providing mutual aid either at the scene or in coverage were Keasbey, Hopelawn, Fords, Sayreville, South Amboy, Port Reading, Iselin and Colonia.
The city fire department and the Middlesex County Fire Marshal’s Office were investigating the cause.
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