A woman's body was found Wednesday in a building stairwell on the grounds of San Francisco General Hospital, authorities said.

San Francisco Department of Health spokeswoman Rachel Kagan said the body was found around 1 p.m. by a staff member in a power plant building. She said the coroner was investigating the cause of death and the woman's identity had not been determined.

Kagan said there were no missing person reports of patients. Kagan said only employees have access to the building and investigators were trying to determine how the woman gained access. She did not say how recently the hallway had been checked by security officers.

Five years ago, the body of a missing patient was found in a stairwell at the same hospital, more than two weeks after a patient disappeared from her room.

An autopsy determined that 57-year-old Lynne Spalding had been dead for several days before her body was found in a stairwell that was supposed to be routinely checked by security.

The Sheriff's Department, which is responsible for the hospital's security, paid Spalding's family $3 million to settle a legal claim.