According to arrest warrants, Thomas told officials he saw Eleby start the blaze.
"Mr. Thomas watched Basil Eleby place a chair on top of a shopping cart, reach under the shopping cart and ignited it," the warrants said.
But Eleby said he “left the area before the fire started.”
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What are the charges?
Atlanta I-85 Collapse: Suspect Spoke of Smoking Crack, Warrant Says
Basil Eleby, 39, was charged with arson, first-degree criminal damage to property and criminal trespass. Sophia Bruner and Barry Thomas were charged with criminal trespass.
Judge James Altman set Eleby's bond at $200,000 during a brief appearance Saturday morning in Fulton County Magistrate Court.
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Warrants suggest Eleby was using drugs before the fire.
According to arrest warrants, Eleby admitted to being in the area of the fire around 4 p.m., where he “discussed smoking crack cocaine” with the other suspects.
Eleby has an extensive criminal history.
According to Fulton County jail records, Eleby has been arrested 19 times since 1995, mostly on drug offenses. He was last arrested in 2014 in Fulton County for the sale and trafficking of cocaine.
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All three may have been homeless.
Authorities said Eleby, Bruner and Thomas may have been homeless, although it is not clear whether they had lived at the site beneath the highway.
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Return to AJC.com for updates.