The blaze broke out around 1 a.m. Wednesday, May 12, in New Haven, on Valley Street, officials said.
New Haven Mayor Justin Elicker said the firefighter was killed battling the fire, and three others, who had to be rescued, were injured, including one critically.
"One firefighter is in the burn unit at Bridgeport Hospital," the Mayor said.
The other two received minor injuries.
A pair of residents were also rescued, but were not injured, Elicker said.
This is a developing story. Check back to Daily Voice for updates.
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