INDIANAPOLIS - Thirty-six homes sustained critical damage in an explosion that killed two people on Indianapolis' south side, inspectors said.

The explosion happened Saturday night at a home at 8349 Fieldfare Way in the Richmond Hill subdivision near Sherman Drive between County Line and Stop 11 roads.

The blast leveled the home where it originated and seriously damaged two homes on either side, all four of which have been ordered to be demolished.

Inspectors have deemed 12 nearby homes unfit for occupancy and unsafe for the homeowners to collect personal belongings until they are stabilized.

Nineteen other homes are also unfit for occupancy, but homeowners will be escorted back inside to collect what they can, officials said Monday.

"They're going to be given one hour to retrieve their belongings, and from there they'll have to leave the premises until Code Enforcement can make a better determination of what to do with the property," said Capt. Rita Burris, with the Indianapolis Fire Department.

Code Enforcement inspectors have color coded the blast area, determining which homes sustained the most damage, which homes should be demolished and which homes should be saved. The city gave Gary Jarnigan the worst case scenario.

"(I'll be) finding some place to live for the next year or however long it takes to totally rebuild my house," Jarnigan said. "So, (I'm) living out of a bag right now."

Robert Stevenson and his wife have moved into a nearby hotel. They're one of the lucky ones who will get to return home.

Meanwhile, Citizens Gas officials said crews were back in the neighborhood running tests Monday. No leaks were found in the main line, and testing individual homes' gas lines could take some time, officials said.

A representative said a meter reader had last been at the home that exploded on Oct. 26. Consumption was normal at that time, she said.

John Shirley, whose ex-wife and daughter live in the home, told RTV6 on Monday that he believes a faulty furnace may have sparked the explosion after his daughter told him the family was staying at a hotel because the heat was out.

Authorities have not said what they believe caused the explosion, but Mayor Greg Ballard said investigators have ruled out a bomb, a methamphetamine lab and an airplane crash.

"It's a methodical investigation. You have to go step by step, and you have to know what you're looking for," said Indianapolis Department of Homeland Security Chief Gary Coons.

The Bureau of Alcohol, Tobacco, Firearms and Explosives and the National Transportation Safety Board, which oversees gas lines, were called in to help with the investigation.

A Greenwood elementary teacher and her husband who lived next door to the house that exploded were killed and eight people were injured in the blast and ensuing fire, which displaced at least 200 people.

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