INDIANAPOLIS (AP) — A deafening explosion that leveled two homes and set two others ablaze forced about 200 people from a devastated Indianapolis neighborhood overnight. Authorities said one body was recovered after the flames were extinguished from the blast that shattered windows, crumpled walls and did other damage to dozens of other homes.

Two people were taken to a hospital with minor injuries, said Lieut. Bonnie Hensley, with the Indianapolis Fire Department. But she cautioned authorities were going through the rubble and conducting a house-by-house search for anyone else in the hours before dawn.

"This looks like a war zone; it really does," Hensley told The Associated Press. "Police officers and fire department officials remain at the scene searching for other possible victims. They've brought in search lights as they look through the ruined homes."

She declined to identify the only confirmed fatality, saying only that the body was found in one of the leveled homes.

The explosion at 11 p.m. Saturday destroyed two houses that were side by side and spread fire to two other nearby homes in the neighborhood on the south side of the city, she said. The blast was heard for miles all around.

She added that at least two dozen other homes on blocks all around were damaged by flying debris from the leveled homes — as well as from the shock wave from the blast.

Many people were asleep at the time and had to be evacuated in pajamas, scooping up their pets as they left hastily, authorities said. They left what some described as a chaotic scene of tall flames rising on the Indianapolis skyline.

Survivors reported shattered windows, caved-in walls and garage doors knocked off their hinges. And of the two homes that were leveled by the blast, Hensley said: "There's nothing left."

Complicating the pre-dawn search of the neighborhood, authorities did not know definitively how many people were in the neighborhood when the blast occurred. "People scattered when all this happened, so we're not really sure how many people we're looking for," Hensley said.

Bryan and Trina McClellan were at home with their 23-year-old son Eric when the shock wave from the blast a block away shuddered through their home. It knocked the windows out along one side of their home and their first instinct was to check on their two toddler grandchildren in the basement. One was holding his ears and saying "Loud noise, loud noise."

Eric McClellan said he ran afterward to the scene of the explosion and saw homes leveled or nearly so.

"Somebody was trapped inside one of the houses and the firefighters were trying to get to him. I don't know if he survived," he said, adding firefighters were trying to save a man.

He said he didn't know the man's fate as firefighters ordered him to leave.

The cause of the explosions remains unknown, authorities said. Investigators were expected to better assess the rubble after daybreak for clues to what happened. Meanwhile, all power, gas and other utilities were shut off as a precaution as emergency officials swarmed the site.

Approximately 200 people were taken to an elementary school where only about 15 to 25 remained through the night, sleeping on cots. Most of the evacuees subsequently left to stay with relatives, friends or at hotels.

The powerful blast caught sleeping people unaware.

Pam Brainerd, a 59-year-old hospice nurse, said she was asleep on her couch when the tremendous explosion rocked the neighborhood, blowing out the upstairs windows in her house.

"I was sleeping on the sofa and all of a sudden, my upstairs windows were blowing out and my front door was falling in," Brainerd told AP. "My front door came off the frame. It was the largest bang I've ever heard."

Right after the explosion she stepped outside to see what she described tall flames one street away. "There was a house engulfed in flames and I could see it spreading to other houses," she added.

At the elementary school, authorities sought to impose order and calm on an initial scene of confusion.

Some evacuees milled about the elementary school in pajamas and coats they grabbed as they left their homes. Some had their dogs on leashes and one lady had evacuated her home with a cat. Beyond the school's parking lot, smoke was still visible, rising in the distance before dawn. The smoke was illuminated by bright lights of emergency responders.

The cause of the explosion and fires wasn't immediately clear, but Indianapolis Mayor Greg Ballard immediately squelched initial speculation of a possible plane crash. "It was so strong that it clearly had an effect for blocks," Ballard said while grey clouds of smoke still billowed after the fires were contained.

While some questioned whether natural gas was suspected in the blast, he said he had no preliminary information on a possible cause. He said it was still a time for taking care of those forced out.

"We're going to need some comforting in the next few days," Ballard added.

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