MINNEAPOLIS (WCCO) — Charred debris and police tape still remain where two girls were seriously burned in a parking lot fire Tuesday morning outside a Walmart in Fridley.

Police say the blaze somehow sparked from a white van around 7:15 a.m. outside the store on University Avenue. The flames quickly spread to the vehicles parked on either side, including a minivan with two young sisters, ages 6 and 9, inside. Their mother was shopping inside the store when the fire started.

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The owner of the van that initially caught fire was arrested on probable cause for negligently causing a fire, which is a felony. There was also a woman in that vehicle, but she managed to get out without any major injuries.

Kathleen Kapps works with the mother of the two girls.

“When I got to the scene and when the firefighter told me what happened, I wanted to hit the ground. I’m still trembling in my stomach, it’s really rough,” Kapps said.

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She says the children were in her mother’s Universal Transit work vehicle when the fire broke out. The company transports students to school districts throughout the metro.

“God bless her children. I hope they are OK,” Kapps said.

Those two girls suffered burns all over their bodies and smoke inhalation. They were both listed in critical condition at Hennepin Healthcare as of Tuesday night.

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The man who was arrested is expected to be charged Wednesday.