SAN FRANCISCO (KGO) -- Ed Lee is not the first San Francisco mayor to die while serving out his term.
RELATED: San Francisco Mayor Ed Lee passes away at age 65
The last time it happened was in 1978 when the death of then Mayor George Moscone rocked the entire city.
Their deaths were very different, but what followed could provide some important lessons for new acting mayor London Breed.
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VIDEO: Who is acting San Francisco Mayor London Breed?
The death of SF's mayor 39 years ago that shook the entire city