KUSA - On Saturday, a clearer picture emerged of what happened inside Arapahoe High School on Friday when a high school student opened fire, shooting one student and eventually turning the gun on himself.
Arapahoe County Sheriff Grayson Robinson says security cameras at the school were instrumental in their investigation into Friday's shooting.
Even though shocking situations can sometimes feel like they are going in slow motion, cameras showed just one minute and 20 seconds elapsed between when the gunman entered the school and when he shot himself in the library.
During that time, senior Claire Davis was shot in the head, and a Molotov cocktail was detonated in the library. It started a fire.
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