CCTV footage has been released showing the moment last week’s disastrous Chevrolet dealership fire started in Sterling Heights, Michigan.

The video shows a contract cleaner washing the floors of the dealership’s service center in the moments leading up to the blaze. After making several passes on one section of the floor, the cleaner accidentally knocks over a fuel tank resting on its side.

Petrol starts to leak into the service drain as the cleaner goes directly over it, instantly causing a massive fireball that quickly spread across the floor.

In his frantic call to 911, the man describes the frantic scene saying, “I was scrubbing the floor and I don’t know something was leaking gas and it caught fire. I have severe burns on my arm… There’s a car in the shop on fire. Sh** is blowing up I need people here now.”

The fire soon took hold and by the time authorities extinguished the inferno, at least 30 vehicles had been destroyed.

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