THORNTON - An RV in a King Soopers parking lot exploded early Saturday afternoon.

The incident occurred at the King Soopers on East 120th Avenue and Colorado Boulevard in Thornton.

The Thornton Fire Department responded to the scene and believe the explosion is accidental.

Thorton Police say the RV had been broken down for several days, and the family had been working on the fuel pump when the fire began.

Witnesses say they saw smoke coming from the parking lot, when the RV suddenly exploded and burst into flames

Amazingly, witnesses say nobody was injured from the blast.

One car suffered heat damage from the explosion, according to fire officials.

Gena Pasley said she had been doing some shopping in the area when she first noticed the smoke.

"We saw some smoke going in the air -- just a little tiny bit -- so we went across and went on over to King Soopers and as we were at that intersection we heard an enormous explosion," she told 9NEWS.

She said a family and their two cats had been living in the camper, and that they were able to escape unharmed.

Another witness captured dramatic video of the flames, showing the camper is likely a total loss.

"The blazes started getting higher and higher and black smoke started billowing out," Pasley said.

"They got worse. The flames just engulfed the entire camper."

Pasley said nearby businesses are helping the family.

Pet Ranch donated a cart the family could put the two cats in, along with a cat litter box and food.

Supercuts provided a hair product care package: shampoo, conditioner and hairbrushes.

"When you have something that belongs to you and you lose it in such a shocking way, that's just heartbreaking," Pasley said.

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