Updated 4:33 p.m. ET: CHARLESTON, W.Va. -- Eight people, including a woman celebrating her 26th birthday and six young children, were killed early Saturday when fire swept through a two-story home while they slept.
A seventh child was also hurt in the blaze, which was reported around 3:30 a.m., and was in critical condition.
It was not immediately clear what caused the blaze, which appeared to have started in a front room on the first floor.
When firefighters arrived, the house was fully engulfed in flames, said Bob Sharp, assistant chief for the Charleston Fire Department. They found four people upstairs and five downstairs; all died except for one child. A tenth person escaped to a neighbor's house and called 911, Sharp said.
All of the children who died were 8 years old or younger.
Charleston Mayor Danny Jones said the two-story wood frame home did not have a working smoke detector.
There was one smoke detector in the kitchen but it was installed too low and would have taken too long to activate, Sharp said. Another broken smoke detector was found near the basement - so essentially there were no working detectors.
"That means people couldn't have been alerted," Jones said. "They didn't have a chance."
The victims, some identified by only their first names, were Alisha Carter-Camp, 26; Alex Seal, an adult, age unavailable; Keahna Camp, 8; Jeremiah Camp, Elijah Scott, 3; Kiki, 3; Gigi, 3; and Emanuel Jones, 18 months.
Carter-Camp lived at the home with her children and her sister's children, WSAZ-V reported.
The sister, Latasha Isabelle-Jones, 24, was outside the home when it started to burn and was not injured. A 7-year-old boy, Bryan Timothy Camp, also survived and was listed in critical condition at a hospital.
"We have reason to believe that a lot of the people stayed in the house more than one night and maybe on a weekly basis," Jones said. "These people may have had residences in other places, but a lot of people lived in this house."
Carter-Camp's 26th birthday was Saturday, and a party was being held at the home for her, authorities said.
People started showing up for the party around 2 p.m. Friday and it started outside an hour later with a cookout and toasts to the birthday girl.
"They were nice people drinking a glass of wine," said Roxie Means, who attended the party Friday her 14-year-old daughter, Cassie. "They weren't drunk. They weren't overdoing anything."
And before she left, Carter-Camp's two children wanted to know if she would be back on Saturday.
"I was telling the kids good night," Cassie Means said. One of the children asked her, "'Cassie, are you coming over to play with us tomorrow?' I said, 'yeah.'"
The child continued, "'you promise me you'll be here tomorrow?'" Cassie Means recalled. "I said, 'I promise you I'll be here when you wake up to play with you. I'll be here right when you wake up."
Hours later, the only adult survivor was smoking a cigarette outside, noticed the fire and came running to Means' home and started "beating down the door," Roxie Means said.
Investigators believe that all of the victims were asleep at the time of the fire and died of smoke inhalation.
Jones said it was the worst house fire Charleston has ever seen in terms of loss of life. In 1949, a fire at the Woolworth department store in downtown Charleston killed seven firefighters, according to the Gazette.
The Associated Press contributed to this story.
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