Demonstrators calling for the removal of the city's police chief drowned out Gov. Jerry Brown as he administered the oath of office to Lee before hundreds of guests at San Francisco City Hall. The protesters booed and shouted throughout the hourlong ceremony, disrupting Lee and other speakers and the posting of the color guard.
But the mayor carried on, praising San Francisco's diversity and vowing to keep the city a place for newcomers and old-timers alike.
His critics say he has done just the opposite in his five years in office, courting new tech money while ignoring the city's stubborn problems with homelessness and a lack of housing.
Lee also faces fallout from the Dec. 2 shooting death of Mario Woods by five police officers in the city's gritty Bayview neighborhood. The officers say he refused commands to drop an 8-inch knife.
Lee remarked Friday that 2016 in the Chinese calendar is the year of the monkey, and people born in such a year are optimistic and energetic.
"They are confident, inventive, but they are also restless," Lee said. "That sounds, I think, a lot like San Francisco."
About 75 protesters were at the event, said Eileen Hirst, chief of staff of the San Francisco Sheriff's Department. Ten were detained and escorted out, but there were no arrests.
"There was a lot of noise but certainly no violence," Hirst said.
The protesters yelled for the firing of Police Chief Greg Suhr. At one point, Lee addressed their chants with, "Thank you. We heard you."
Dian Wolfwood, 20, was among those booted from the building. He said police need to be held accountable.
This is Lee's third swearing-in. He was tapped in January 2011 to fill the remainder of now-Lt. Gov. Gavin Newsom's term.
Lee won re-election in November with 55 percent of the vote, a lackluster figure given that he faced five unknown candidates. In comparison, Newsom captured more than 70 percent of the vote when he faced a similar slate of unknown challengers in 2007.
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