SAN FRANCISCO (CBS SF) -- A woman, whose body was found in a stairwell of the power plant on San Francisco General Hospital's campus, had been reported missing by an elderly care facility located there on May 20, officials said Thursday.
San Francisco Sheriff Vicki Hennessy said 75-year-old Ruby Andersen signed herself out of the behavioral health facility on May 19th and was expected to return by 4 p.m. But she never returned and deputies were called at 1 p.m. on May 20.
"We were contacted...by a team leader from the behavioral health center on the campus of San Francisco General," she said. "A resident of the residential care facility for the elderly, which is a board and care facility, left at 9 a.m. the day before and indicated she would return at 4 p.m. It's clear that people can sign themselves out and sign themselves back in."
A deputy responded, took a report and tried to call two members of Anderson's family, but did not get a return call until May 22nd. He checked with the General Hospital staff to see if Anderson had been admitted and also called the medical examiner's office.
Hennessy said the deputy also entered a missing person's report.
Deputies check every "nook and cranny" if a hospital patient is reported missing but there is no protocol for the same situation at the residential care facility of the Behavioral Health Center, which is run by the city's public health department, said Hennessy, whose agency is responsible for security at both facilities.
"We're going to be reviewing everything to see where the holes are because it looks like we need to do better," she said.
The 50-resident care facility serves people with mental conditions who are 60 and older and need non-medical support, including ensuring they take their medications and eat properly, said Kelly Hiramoto, director of the Behavioral Health Center.
On Wednesday 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.
Authorities still can't account for Anderson for the 11 days in between when she departed the residence center and when her body was discovered.
Roland Pickens, the head of the San Francisco health system, said an autopsy was scheduled to determine when and how Anderson died. He said there was open entry into the power plant building where her body was discovered between 6 a.m. and 6 p.m. each day.
Unfortunately, Pickens said, there were no security cameras in the area of the campus where Anderson disappeared.
Hennessy said the medical examiner was called to the scene and determined there was no need to call for a homicide investigation.
"We're very concerned that this happened and we don't know how this woman gained access to where she was found," Kagan said.
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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