Dozens of cars went up in flames, causing their tires to explode, inside the Kings Plaza Shopping Center parking garage in Brooklyn on Monday.
The vehicles burned on the second and third floors of the parking garage in Marine Park. Officials say there were as many as 120 cars being stored in the structure by a local car dealer.
WATCH: NYC Fire Commissioner Daniel Nigro briefs reporters on the fire
Investigators say 23-year-old Avon Stephens was caught on surveillance video leaving the Kings Plaza shopping Center parking lot before Monday morning's fire.
Stephens, believed to be homeless, was previously told by security not to sleep in the garage, but he later allegedly managed to break into one of the cars.
He was taken into custody later Monday evening and arrested on a charge of arson. Officials say he allegedly confessed to sparking the fire and apologized.
Records show he has prior arrests, including for an attempted robbery.
Stephens said very little during Tuesday's court appearance and covered his face with his hand. He was ordered to remain behind bars without bail until his next court appearance.
Monday's blaze left 18 firefighters and three civilians injured after upwards of 300 FDNY firefighters responded to the scene.
"None of these 21 injuries is life-threatening or critical, everyone is stable," the FDNY said. "Our members have various levels of smoke inhalation, heat exhaustion, working under those conditions. Smoke and heat, wearing what they wear, one can only imagine what they are going through."
Kings Plaza reopened to customers Wednesday after being closed Monday and Tuesday due to the fire and smoke conditions in and around the mall.
"We are not sure yet how many of them burned, but many of these cars were involved in this fire, creating, if you were here earlier, a huge amount of black smoke, a very large amount of fire, confronting our people," the FDNY said.
Anyone with additional information is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477)
WATCH raw video from the fire scene
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