The fire started in the kitchen of a three-story Lancaster duplex at about 3 a.m. after frozen potatoes were placed in the oven, fire officials said.
Officials say three of the victims were adults and three were children. A 2-year-old also remains in critical condition.
One victim was identified by fire authorities and a relative as the homeowner, 65-year-old Jimmie Moore.
"Rest in peace, Dad," one of Moore's daughters, Cyrena Brock, 34, told The (Lancaster) Intelligencer Journal. "He was a hero to me."
Fourteen members of several families lived in the home, which didn't have smoke detectors, Gregg said. Fire crews got the flames under control in about an hour, he said.
Neighbors and relatives described Moore as a generous man and Vietnam War veteran who let another family move in after they lost their own housing.
"He was a very friendly man," neighbor Molly Lalla told the newspaper. "He would walk down the alley and say hi and wave. He brought a box of toys to my kids."
Ken Sheetz said Moore was the first one to welcome him to the block when he moved there.
"He was a caring person," Sheetz said. "He loved his family."