The incident took place in Bridgeport around 6 p.m., Tuesday, June 6 on Mountain Grove Street, said Scott Appleby, director of emergency management for the city.
The fire started when a line of storm cells passed through the area, Appleby said.
The lightning struck the chimney causing moderate damage to the roof and third-floor apartment ceilings, he added.
Initial 911 reports indicated a fire in the basement however, no fire was detected.
There were no reported injuries and Red Cross is assisting 10 adults, one child, and six pets.
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