CHICAGO (CBS) — A 7-year-old boy has died days after an apartment fire that left another person dead and three others hurt in the South Shore neighborhood.

The fire broke out inside the three-story apartment in the 2400 block of East 78th Street around 2:30 a.m. Saturday.

One person, a 24-year-old man, was found dead at the scene.

Four other people, including two boys, 2 and 7, were taken to hospitals.

The children were taken to Comer Children's Hospital. The 7-year-old was initially listed in critical condition but later died. He was identified as Adrian M. Matias by the Medical Examiner's Office.

The 2-year-old was last said to be in good condition.

A 27-year-old man was taken to Trinity Hospital, and a 24-year-old woman was taken to the University of Chicago Medical Center. Both were also listed in good condition.

Twenty-three people were displaced as a result of the fire.

The cause of the fire remains under investigation.