An extension cord overloaded with Christmas decorations may have sparked a fire that swept through four downtown row houses Friday, killing five people and injuring several others, officials said.

The holiday decorations had been plugged into a power strip joined to an extension cord, said Allentown Fire Capt. Robert Scheirer.

He said the early morning fire was ruled accidental, though investigators were still trying to determine if the wiring failed, a specific ornament shorted out or if something else was involved.

The three-story row home had no working smoke alarms. Three men and two men died inside, Scheirer said.

Firefighters were able to get the 6:30 a.m. fire under control within about half an hour. They also rescued two adults and six children from a row house next-door; the conditions of those injured at the home were not immediately released.

The other row homes among the four that burned were either vacant or the people inside escaped on their own, Scheirer said. Four other houses on the street were damaged by smoke.

"I got woken up by people screaming 'Fire!"' said Rafael Canizares, 40, who lives a few doors down and fled with his mother in the pre-dawn darkness. He said he saw flames coming out of several houses and several front porches ablaze.

The victims' identities were expected to be released later Friday, the Lehigh County Coroner's Office said.

Brenda Pun, 41, said she knew one of the victims and described her as a generous person who was active in the community.

"I just talked to her yesterday," Pun said as she stood outside the home. "She would give to anybody, no matter what they needed."