Washington, D.C., Mayor Adrian Fenty says an 11-year-old boy critically injured in a fire that killed five people New Year's Day is clinging to life.

The electrical fire began in the basement ceiling and raced through the two-story home in northeast Washington. The blaze killed a 5-year-old girl, her parents and two others.

The mayor says it was the deadliest fire in Washington in three decades.

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Fire officials believe the house was built in the 1940s or 1950s, and the style of its construction was meant to allow heat to pass easily from room to room, Fire Chief Dennis Rubin said. The design also allowed the fire to travel rapidly through the structure, he said.

"This type [of] home would not be allowed by code today," Fire Chief Dennis Rubin said. Officials hadn't determined whether smoke detectors were working.

The dead were identified as Keith Nelson, 23; Tawanna Gant, 22; their 5-year-old daughter, Kaniya Gant; Joseph Wilson, 10; and Charles Smith, 72. Authorities were not sure of the relationship between the boy, the older man and the other victims.

Neighbor Mary Meeks said she awoke to see flames shooting out the windows of the home's basement. She ran from her home across the street and started banging and kicking on the front door, and her daughter called 911.

"I didn't hear any movement," Meeks said. "That's why I was banging on the door, but I still didn't hear anybody."

Along with the critically injured boy, a 44-year-old man, a 41-year-old woman and a 15-year-old boy were hospitalized with non-life-threatening injuries, officials said.

About 120 firefighters put out the blaze.

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