Firefighters were called about 12:20 a.m. and found heavy smoke on the third floor of the senior facility in the 2800 block of Elisha Avenue, the Zion Fire Department said in a statement.
Carmel House Senior Apartments is located on that block.
Crews evacuated nearby units and extinguished the fire in the room it started, the release states.
One person was taken in serious condition to Vista East Medical Center, and two people were taken for underlying medical issues that may or may not have been exacerbated by the incident, the release states.
Because of the smoke, authorities evacuated all of the building’s occupants to Zion City Hall, which is in the same block where the fire occurred.
About 55 firefighters and 25 vehicles, including from neighboring departments, assisted in the response.