MEMPHIS, Tenn. (AP) -- A cleaning woman who was trying to light a cigarette inside her car instead ignited fumes from cleaning products and caused an explosion that blew out the vehicle's windows and sun roof, police said.
The woman, whose name wasn't released, suffered first- and second-degree burns on her face, arms and neck and was treated at a local hospital.
"It was just a freak accident," Memphis Police Director Larry Godwin said.
It had looked more serious earlier in the day when the blast was reported about noon in an office building parking lot on the east side of the city. It was the second time in a month that authorities responded to the report of a car explosion in the Memphis area.
Godwin said the woman had a lot of cleaning chemicals, including bubble gum remover, in the trunk of her car.
"We got a flash, a vapor-type flash. That's why you see a push on the doors and windows," Godwin said.
He described it as a "dangerous situation" that resembled a bomb detonating.
Dana Swift, a dental assistant at Memphis Periodontal Group across the street from the blast, said she heard a loud boom and rushed outside to see what happened.
"We didn't know what happened. We are located right by a railroad track so we thought the train might have hit something," Swift said.
Dr. David Shainberg, a physician with offices across the street from the blast, went to the parking lot after he heard the explosion. He saw a woman beside the car who had what appeared to be an injured arm and soot marks on her face.
She was distraught and disoriented but didn't appear seriously injured, Shainberg said.
"She was walking and talking, but she was physically upset," he said.
Fire officials and bomb experts from the city police and federal Bureau of Alcohol, Tobacco, Firearms and Explosives conducted the investigation.
Authorities blocked off streets surrounding the parking lot, and many people who work in the area were on lunch break when the explosion occurred and couldn't get back to their offices for a while, Citadel Memphis Radio Group switchboard operator Rita Martinez said.
Dr. Trent Pierce, 54, is still hospitalized and authorities have not made an arrest in that bombing. Pierce lost his left eye and remains unable to talk because of an oxygen tube in his throat but communicated with ATF agents during a visit last week, West Memphis police said.