BRIGHTON, Colo. — Brighton police have taken over the investigation into the fire that destroyed the historic Arthur Grain Mill after it was determined it was sparked by a discarded cigarette.

Brighton Fire Rescue said in a Tweet Tuesday that someone sleeping in the abandoned building discarded the cigarette and it started the fire on Feb. 8.

The historic Arthur Grain Mill was a total loss following the second alarm fire at the building near Denver and North Main Street in Brighton.

On the day of the fire, Brighton Fire Chief Mark Bodane said there had been reports that some people experiencing homelessness might have been living in the structure before the blaze broke out.

Temperatures that Friday morning hovered just above zero, something that Bodane said created challenges for firefighters.

Amanda Kinzie works just a few blocks away from the structure. On the day of the fire, she told 9NEWS the building had been vacant for quite a few years but has a lot of history for locals.

"It's a memorable place for us here in town," she said.  "For the farms, people who grew up here, we used to buy our feed from that place."

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