SACRAMENTO COUNTY (CBS13) – Fire crews are investigating what caused a fire to inside a gas station car wash overnight.

Sacramento Metro Fire crews say they received multiple calls from passersby about a fire at the Shell gas station car wash on Folsom Boulevard near La Riviera Drive.

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When crews arrived they found flames coming from both the front and back of the car wash.

“So I ran back inside, had the manager call the fire department, ran back outside to make sure everyone was away from the fire,” said gas station employee Michael Black.

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Crews quickly knocked down the flames, which did not damage the 7-Eleven store nearby.

Barbie Law, the Metro Fire battalion chief on scene, says this type of fire is a bit strange.

“We called out an arson investigator because it was obviously odd to have a car wash fire in the middle of the night,” Law said.

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The exact cause of the fire and the amount of damage done is under investigation.