A ranch home in the 800 block of Martin Drive on Elgin's southeast side was rendered uninhabitable after a fire Thursday afternoon, authorities said.

No one was injured in the fire, which was reported at 2:12 p.m. by a grandmother watching her 4-year-old grandson.

Elgin Fire Department Battalion Chief Terry Bruce said the boy told the woman there was a fire in his bedroom.

Rescue crews arrived three minutes after the woman called 911 and had the fire under control in about 10 minutes, officials said.

"The grandmother found it, closed the door and got everyone out of the house. For a while, that did hold the fire," Bruce said. "I feel bad for the family. It caused a lot of damage."

Bruce said the fire went out through the bedroom window and into the attic, causing at least $40,000 damage.

Bruce said investigators are interviewing the grandmother and boy, who were the only two people home at the time. The cause of the fire is not believed to be suspicious.