COOPERTOWN, Tenn. -- An off-duty EMT and a retired volunteer fireman helped a Coopertown woman rescue her two grandchildren from her burning home Monday.

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The three-alarm fire happened on Errell Dowlen Road in Robertson County, officials said.

Firefighters said it took about four hours to completely put the fire out.

The house was fully engulfed when firefighters arrived, neighbors said.

They said that 51-year-old Gayle Gilley came running across the street screaming that her house was on fire and that her grandchildren were still inside.

Neighbors said an off-duty EMT ran into the house to help Gilley rescue her 4-year-old grandson.

Officials said Gilley then ran back inside the house to get her 6-year-old granddaughter and that that is when former volunteer fireman Randy Drake said he crawled into the burning house and shouted for her.

Drake said it was hard to see because of all the smoke but that he was able to grab Gilley and her granddaughter and pull them to safety.

Neighbors said they believe the house was about 100 years old and used to be a log home, which made it harder for firefighters to put out, firefighters said.

“The house is an older house. (It has) been added onto several times, so there’s a lot of void space, so the firefighters are having a tough time trying to find some of the fire. It has been a tough fire, no doubt,” Assistant Fire Chief P.J. Duncan said.

Firefighters said due to the extent of the fire, they could not tell if there were smoke detectors inside the home.

“Well, I mean, the safety measure you can get out of here is that we’ve got three critical. You know, check your smoke detectors, no doubt. Make sure the batteries work. Make sure the smoke detectors are working. Make sure you’ve got one in each bedroom and one on each floor,” Duncan said.

Duncan said he doesn’t advise anyone going into a burning house but that he understands why Gilley did.

“The grandmother had the instinct just like any other parent would. I mean, I would have done the same things if my kids were in there that she did. I’m sure in that situation, she probably did the right thing, because she went back in and got the kids,” Duncan said.

Drake said that when he went back in that flames were shooting out of the kitchen door like a blowtorch.

Gilley and the two children were taken to Vanderbilt University Medical Center.

Gilley and one of the children are in critical condition and the other child is in critical but stable condition, officials said.