Two other people were hospitalized in very critical condition, Chicago Fire Department spokesman Larry Merritt said. Fire Commissioner Jose Santiago told reporters that one of the children who died was an infant. Officials have not released the names or ages of the victims.
"We have not had this in many, many, many years — this amount of fatalities and injuries in one location," Santiago said.
Officials say firefighters were called around 4 a.m. to the fire in the largely Hispanic Little Village neighborhood on the city's southwest side. At least two buildings caught fire, one of them a coach house. The cause of the blaze hasn't been determined.
Video showed smoke coming from windows of the three-story building's stone facade, with flames engulfing the coach house at the back. Police officers helped push a stretcher toward an ambulance, while a paramedic simultaneously performed CPR. One woman lay on a street crying while someone tried to comfort her.
Those killed were all from the same residence, Merritt said. He said investigators have not found working smoke detectors.
At least one firefighter was injured and was hospitalized in good condition.