Camden County's spokesperson said careless smoking ignited the inferno at the Mansion Apartments on the 200 block of West Branch Avenue Tuesday evening.
Nearly 30 people were displaced as a result of the fire.
Five police officers and a firefighter were taken to an area hospital to be treated for smoke inhalation.
Crews were able to get the blaze under control at 8:20 p.m. No residents were injured, police said.
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