Capt. James Romaniello said the cause of the three-alarm fire was still being investigated.
The fire was reported shortly after 1 p.m., and it took about two hours for firefighters to fully extinguish the blaze, he said. The firefighter injuries were minor, he said.
"One of the ladders slipped and it grazed the side of his face. It was a glancing shot," he said about one injury. The second firefighter was treated for heat exhaustion, he said. Both were treated on the scene and cleared, he said.
He said the fire is believed to have begun in the basement of 38 Lockwood and then spread to 40 Lockwood and went up through its first, second and third floors.
Romaniello said at least six residents are being relocated, but he said it was still uncertain as of Friday afternoon whether there were additional occupants at the location.
The Red Cross has been called in to assist.
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