Sumter, SC (WLTX) - The Sumter Fire Department says one person is dead and another injured after an overnight fire on Franklin Street.

Eva Harvin, 68, of Sumter died as a result of the fire, according to Sumter County coroner Robbie Baker. An autopsy will be performed in Newberry.

Her 71-year-old husband was severely burned and flown to the Augusta Burn Center.

The couple lived in their house with their son, who was not home at the time of the fire.

Battalion Chief Joey Duggan says they received a call just after 1 a.m. Thursday.

While the cause of the fire is unknown, Duggan says they know where the fire originated.

"We had our fire investigators come in," says Duggan. "They looked at the origin and cause and determined that at this point that it started in the attic around the heating and air unit. They didn't say if it specifically started at the heat and air unit, but it was around that area."

The fire investigation has wrapped up and Duggan says the fire has been ruled as undetermined.

"It could have been an electrical issue, " says Duggan. "It could have been any number of things which could have been an issue, but we do see a lot of heat related fires during this time of year."

He estimates $75,000 in damages to the home.