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WAXAHACHIE (CBS11) – In Waxahachie, homeowners worry and they wait. They worry about what touched off an explosion so powerful that it leveled a home in the 100 block of Arabian Road this morning, while damaging nearly a dozen more.

“Black smoke and debris flying everywhere,” says JoAnn Williams, who lives nearby. Williams was one of the many neighbors rushing to help pull two people believed to be adult siblings, a brother and sister, from inside the burning home. They were taken by air ambulance to Parkland hospital in Dallas.

“It looked like her entire roof was on top of her,” says Robert Denton, “we had to move a bunch of boards, a bunch of debris.” Denton says he didn’t stop to think about the danger as he headed toward the sound of the explosion. He wanted to help and he did. But, he couldn’t have anticipated the horror that he would also find.

“Never gonna get that visual out of my head,” recalled a sober faced Denton, “she was completely burned, skin melted off, face swollen… it was bad…never seen anybody like that.”

The houses closest to the explosion were also heavily damaged. According to Waxahachie Fire Chief Ricky Boyd, structural engineers will need to be brought in to determine if homeowners can safely return—even to collect belongings. Nearly a dozen other homes were also damaged— with broken windows, doors, bricks and sheetrock. Those families were evacuated immediately following the blast. More homes were added to the evacuation zone late afternoon, officials said, as a precaution.

And they also wait. Officials said they hoped to allow homeowners back in by tonight. But, so far, they are still waiting.

Homeowners tell us that there had been neighborhood talk of gas leaks for the past several days. Many wondered if all of the digging to lay utility lines could have played a role.

Local fire officials so far say, “no.”

“There’s no evidence of that,” says Chief Boyd, “there’s no backhoes doing any digging. None of the boring that was going on, none of that was going on while we were here.”

Following the explosion, Atmos Energy dispatched crews to conduct what they call ‘leak tests’ but, say it is too soon to say whether they found any or what caused the house to explode. But, some neighborhood rescuers may have some clues.

“The whole time we were trying to help her out, we smelled gas,” says Denton, “no telling if it was going to explode again or not.”

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