Firefighters were called to the 600 block of Kimball Street around 1:10 a.m. where they found heavy smoke pouring from a home.
Fire crews had some difficulty accessing the home on the small alley street. They were forced to lay fire hose a long distance in order to contain the fire.
The four residents inside the home were able to escape. All four suffered from smoke inhalation and were taken to Jefferson Hospital for treatment.
No word yet on what sparked the blaze.