PIEDMONT, Okla. - A couple came home from a five-day vacation to find a mysterious "X" scorched into the ceiling of their truck, and what caused it is a mystery.
"I'm like, good Lord! That could have burned down the truck and the house!" said Tama Gannaway.
The burns left a black soot residue across the ceiling, even the molding is melted.
"You know Zorro would mark the 'Z,' Gannaway said. "This looks like an 'X' has been burned into the car. It's insane."
The doors were locked, the windows were up. The couple couldn't figure out what it was.
"The only thing he could find was the water bottle in the seat and sunglasses," Gannaway said.
Then she saw articles online about water bottles starting fires in cars in other parts of the country.
"I thought, 'Oh my gosh, this is probably what caused it,'" she said.
She posted photos online as a warning to others and the post was quickly shared dozens of times.
Oklahoma City Fire Battalion Chief Benny Fulkerson ran a test for News 4 using a water bottle and an old couch cushion.
A thermal imaging camera showed the spot hit by the magnified increased in temperature from 148 degrees to 220 degrees and even started to smoke in about a minute. It would have gotten even hotter had he left the heat on it.
Fulkerson said it's not something he's ever seen on the job.
That magnifying effect requires conditions to be just right.
But just because it's uncommon, doesn't mean it's impossible.
"It can truly be hot enough to cause scorching and scarring of leather or other surfaces," Fulkerson said.
However, in this case, he said he can't be sure the reflection of a water bottle (or the sunglasses) could have gotten hot enough to cause the smoldering burn.
For now, the marks remain a riddle.
"It is scary," Gannaway said. "It is very scary."