They also battled the frigid temperatures, said Middletown Fire Chief Paul Lolli.
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Deputy Fire Chief Jeff Spaulding said investigators are continuing to investigate the cause of the fire. He said more evidence was collected Monday from smoldering material.
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Lolli said there was no power to the building, so the cause of the fire wasn’t electrical, he said.
“So options are limited,” he said.
Neighbors noticed a sport utility vehicle parked near the building, they said. They said the abandoned building was a popular gathering spot for teens and sometimes was entered by others. There was graffiti visible on some of the walls.
Spaulding said anyone with information regarding the fire is asked to call the Middletown police department at 513-425-7701.
The future of the former Middletown business remains uncertain. Middletown officials are expected to meet sometime this week to discuss plans for the building, they said.
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Staff writers Lauren Pack and Mike Rutledge contributed to this report.