SiouxCity, IA – KTIV, By Ike Rayford – Investigators say it was a leak of propane gas that led to an explosion that leveled a Sioux City home early Thursday.

The blast injured three people, one of them, critically.

Investigators sorted through rubble and debris hoping to find an answer to why and how. They now know it was an explosion fueled by propane gas that destroyed the home. A landlord renting the house at 6767 Correctionville Rd. to Greg Raeger said Raeger was thrown from the structure. He’s hospitalized with serious burns. Another man, Mark Murphy, and an unidentified woman were also injured. A neighbor retired Woodbury County Deputy Sheriff Glenn Parrett rushed to the scene to help.

“The female subject and one male subject suffered maybe some minor burns. They didn’t look that severe. The third subject appeared to have second or third degree burns over 80 to 90 percent of his body. The talk was that there was maybe some type of propane leak or explosion something like that had taken place on the first floor,” said Glenn Parrett, neighbor.

Mark Murphy’s sister says the residents of the house reported smelling propane gas Wednesday and reported it. She says someone was scheduled to try finding out what the problem was.

Murphy’s sister says someone was supposed to be at that house Thursday to check on the report of the propane odor. She says the blast happened when someone turned on an oven to cook a pizza.

Officials at Omaha’s Clarkson Hospital told “NewsChannel Four” Greg Raeger remained in critical condition in their burn unit.