The fire broke out around 4:45 a.m. at the Creek Bank Apartments in the 1100 block of Eddystone Avenue.
Authorities say, firefighters arrived to flames showing on the 3rd floor of the building.
Two people were hospitalized with injuries - one of which suffered severe burns.
A police officer was also taken to the hospital to be treated for smoke inhalation.
Officials from the Red Cross tell Action News that about 30 units were likely affected by fire.
They say 25 families (38 people) got financial assistance for food, clothing, and/or lodging.
The Red Cross has set up a reception center for displaced residents at the Light House Community Center at 1401 E. 9th Street in Eddystone.
The cause of the fire remains under investigation.