(Reuters) - Eight people, including six children under the age of nine, died early Saturday in a house fire in Charleston, West Virginia, a fire official said.

All of the victims found in the two-story wood frame house in the state capital were related, though it was not known whether all of them were living together in the home, Charleston Assistant Fire Chief Bob Sharp said.

Sharp said the deaths appeared to be from smoke inhalation, with the bodies found still in sleeping positions.

One child survived and was admitted to the intensive care unit of a local hospital but was "not doing great," Sharp said. He added that five boys and two girls had been in the house during the fire.

The cause of the fire is unknown. It was reported by an unidentified woman who called from a neighbor's house at around 3:30 a.m. EDT (0730 GMT). The woman was taken to the hospital for treatment.

"I've been here 26 years and we've never had anything of this magnitude," Sharp said.

Authorities have not released the names of those killed or injured in the fire.

(Reporting by Mary Wisniewski; Editing by David Bailey and Paul Simao)