SALEM, S.C. — Authorities say an 83-year-old woman has died after she fell through rotting floorboards in a century-old South Carolina house and down a well shaft the owner didn’t know was there.

Oconee County Coroner Karl Addis says it took rescuers nearly four hours Sunday to get the women’s body out of the nearly 50-foot deep hole.

The coroner says the woman was helping her daughter pack up and move from the house in Salem, which according to property records was built in 1920.

Police officers say when she walked across the kitchen floor, part of it collapsed. The woman’s daughter searched for her in the crawlspace under the house and couldn’t find her.

Firefighters found the woman and brought her body back to the surface, said the coroner, who determined she died from injuries from the fall.

Addis declared the death an accident and says he has never seen a death like this in his 31 years as coroner.