The blast ripped off the front of a home in the 6300 block of Algard Street around 1:20 p.m.
During an excavation of the rubble Tuesday, investigators discovered a bullet hole in the home's gas meter, according to law enforcement sources. However, it's still unclear how the bullet got there and whether it is the cause of the explosion.
"It's the scariest thing to walk down and there's no front to your neighbor's house, and you hear him screaming, 'help me' inside. It was horrible," said neighbor Susan Shawcross.
The ATF and fire marshall's office confirmed Wednesday that they are looking at videos posted online, which show the explosion.
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A 61-year-old man was trapped inside after the blast. Good Samaritan, Rakym Dyer, heard the man screaming and ran to help him.
"There was fire on the steps, so I had to put the fire out on the steps first. Then I had to put him out. When I went upstairs he was on fire, so I put him out with the extinguisher, and I put him on my shoulder and I came downstairs," Dyer said.
"People were screaming, 'He's in there, he's in there,'" said Shawcross. "Flames were falling, tiles were falling down, the roof was caving in, but he still ran up there. We thanked him a million times."
Also on the scene was a man who stared in shock at his childhood home, which was reduced to a pile of debris in the front yard. That man, who only identified himself as Michael, said his brother Steven was the 61-year-old man who was rushed to the hospital.
"That just doesn't happen every day. That was my parents' house. I grew up in that house," he said.
He said his home never had any issues such as gas leaks.
Officials say there was a second person evaluated and treated on the scene for smoke inhalation. The 61-year-old victim was last listed as stable at an area hospital.
"I would want someone to help me or help somebody I know, so that's how I look at it," Dyer said. "Here's someone screaming and hollering, saying they're dying, and you want to help them."
On Wednesday, neighbors said they were still thinking about the explosion.
"It was black smoke, the whole sky was black smoke," recalled Betty Silva.
It took an hour to get the fire under control after the blast.