Firefighters responded to a garage fire around 11:50 p.m. in the 8900 block of South Baltimore Avenue in the South Chicago neighborhood, said Chicago Fire Dept. Deputy District Chief Curtis Hudson.
A gas can was found in the garage, Hudson said.
The arson unit is investigating the fire, according to Chicago police.
A 44-year-old firefighter was taken to Advocate Trinity Hospital with a knee injury, Hudson said.