INDIANAPOLIS - A space heater may be to blame for sparking a house fire early Sunday morning on Indianapolis' south side that injured four people, one of them critically.

The Indianapolis Fire Department said the fire was reported at a home in the 3100 block of Alice Avenue just after 1:30 a.m.

Four people were in the home at the time, and all of them suffered injuries, Capt. Rita Burris said. Homeowner George Chapman, 53, was pulled from the house in critical condition and was taken to Wishard Hospital. The other occupants of the home -- Karen Chapman, 50, Justin Kenworthy, 32, and his 5-year-old daughter -- escaped with minor injuries.

Neighbors and Kenworthy were able to pull George Chapman from the fire after he had collapsed near a door, Capt. Rita Burris said.

"Stephen Scrogham, 21, and Brian Boger, 25, along with Jessica Kibler, 30, helped gain entry by kicking in the door. Justin was then able to pull George out of the house and into the yard," Burris said. "Firefighters were just arriving and began immediate medical care."

Kenworthy told fire investigators that he believes a kerosene space heater caused the blaze, Burris said.

Fire investigators said residents should "use caution when using space heaters and ... never leave them on overnight while asleep."