Hartford firefighters received a 911 call around 4:40 a.m. about the blaze at a multi-family home at 62 Adams Street in the Upper Albany neighborhood.
Flames engulfed the home's first floor when crews arrived, but they were to battle them back and get the fire under control. No firefighters were injured in the incident.
Paramedics took one person from the home for treatment. Their condition and the extent of their injuries were not immediately clear.
Authorities said the fire displaced 15 people. The American Red Cross is assisting them.
The cause of the blaze remains under investigation.
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