The two-alarm fire is burning on the 400 block of Jones Street.
San Francisco fire officials say residents have been evacuated, and are working to extinguish the fire on multiple floors.
At least three people are being evaluated for smoke inhalation.
The Red Cross has been called to help.
Drivers should expect traffic delays in the area.
No word on the cause of the fire.
This story is developing. Check back for updates.
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