The blast leveled two houses and spawned fires that burned for hours through an entire row of neighboring homes in Allentown, Pa.
Lehigh County Coroner Scott Grim said Thursday that all but one body had been recovered from the debris. The victims ranged in age from 4 months to 79 years old, fire Chief Robert Scheirer said.
Officials say 47 buildings have been damaged, and eight were expected to be total losses.
Crews had a hard time fighting the fire because one gas line feeding the flames was buried under packed snow and ice.
The cause of the explosion was unclear. The spokesman for Reading-based UGI Utilities Inc. said there is no history of leaks, and there were no calls about gas odors before the explosion.
The Associated Press contributed to this report.