Newark firefighters responded to an apartment fire on Summer Avenue near Van Wagenen Street around 4:46 a.m. today.
Residents from nearby homes, which are closely packed together, were seen sitting on porches after evacuating.
One man was transported to University Hospital for evaluation of breathing difficulties.
The fire was put out by 5:30 a.m. but Summer Avenue remains blocked off to traffic.
A total of eight adults and one child have been relocated.
The cause of the fire and the extent of the damage is unknown at this time.