Two buildings on Vienna Street are involved.
SFFD says three people were rescued and taken to a trauma center. One had moderate injuries and the other two had minor injuries.
One firefighter suffered minor burns but will be OK.
One dog was also rescued from the scene. Another dog, a 7-month-old pup named Star, is still missing.
Firefighters also broke the devastating news to the homeowner that two of her three cats were found dead inside the property.
Stay with ABC7 News for updates on this developing story.
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