Sheriff's deputies monitoring a security camera for the building observed a man breaking glass at the Carlton B. Goodlett entrance's doors, spokeswoman Eileen Hirst said.
Deputies responded to the entrance and saw the man allegedly breaking the glass using his bare fist as well as the butt end of a knife, Hirst said.
The man -- 34-year-old James Weaver -- was arrested and was being booked into county jail this morning on suspicion of nine counts of felony vandalism.
Hirst said that deputies observed that Weaver was "very much under the influence of drugs or alcohol" at the time, although she said authorities had yet to formally determine what may have been in the San Francisco man's system.
People entering City Hall were being asked to use the building's three other entrances that are on Van Ness Avenue and McAllister and Grove streets.
Hirst said the Carlton B. Goodlett entrance was expected to reopen by this afternoon.