The couple says their Hummer SUV was engulfed in flames and the fire was spreading to their other car parked next to it.
"It looked like somebody poured gasoline on it and set it on fire," said Dykes.
Neighbors say they heard a whistle followed by a loud pop before the SUV exploded in flames.
The incident is similar to one that happened on Saturday just a block away when neighbors say they awoke to find another SUV on fire.
Denver Fire investigators aren't yet saying if the two incidents are connected, however, an arson investigation is under way.
Denver Police have also sent their crime lab to both scenes to investigate.
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