SAN FRANCISCO (CBS/AP/BCN) — The daughter of an elderly woman whose body was found at San Francisco General Hospital says she had dementia and disappeared from a nearby health center 10 days ago.

The woman was found Wednesday afternoon in a power plant stairwell. She has been identified by the medical examiner as 75-year-old Ruby Andersen.

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Ruby Anderson Found Dead

Ruby Lee Anderson

However her daughter, Charlene Roberts, said that her mother was 76 and went missing from a mental health facility on the same campus as the hospital on May 20.

Around 1 p.m., an engineering employee discovered the woman’s body inside the stairway of a power plant building at the hospital, San Francisco Department of Public Health spokeswoman Rachael Kagan said.

The building is secure and used mostly by engineering staff, according to Kagan.

The woman’s identity has not been determined and the case is being investigated by the health department, as well as the city’s sheriff and police departments.

“We’re very concerned that this happened and we don’t know how this woman gained access to where she was found,” Kagan said.

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Kagan said that she wasn’t aware of any hospital staff or patients who have been reported missing.

In Oct. 2013, the body of 57-year-old Lynne Spalding was found in a hospital stairwell after she had been reported missing the previous month.

Spalding, a British woman, disappeared after being admitted to the hospital only two days earlier.

According to a report by the city’s medical examiner’s office, Spalding had been dead for some days before being discovered. Her death was ruled accidental, due to an electrolyte imbalance, a condition that can be caused by dehydration.

Spalding’s family filed a lawsuit against the city of San Francisco, which settled the suit for $3 million.

Spalding’s death triggered a set of new security protocols for hospital staff and sheriff’s deputies, who provide security for the hospital.

“That was a terrible tragedy. We’ve made many, many changes since that time and we have no reason to believe that this case and that case are connected, but we don’t know very much about this situation yet,” Kagan said.

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