San Francisco police chief quits amid racism rowSan Francisco's Police Chief Greg Suhr has stepped down hours after a police officer shot and killed a young black woman.
The resignation was announced by Mayor Ed Lee, who had asked him to quit.
The woman reportedly tried to drive off in a stolen car and ignored calls to stop in the Bayview area of the city.
Mr Suhr and city police have in recent months come under fierce criticism over fatal police shootings of several black suspects.
At a news conference on Thursday, Mayor Lee said: "A young woman of colour was killed in an officer-involved shooting in the Bayview (area). The community is grieving, and I join them in that grief."
The woman, 27, who has not been named, was reportedly sitting in a stolen car when a police patrol approached her.
She allegedly tried to drive off and then crashed into a nearby vehicle.
There was no immediate indication that she had a weapon or had tried to run down a police officer before the shooting, the city authorities said.
The San Francisco police department and its chief have recently come under fierce criticism over the death of several black suspects and reports that a number of officers had exchanged racist text messages.
In April, five people went on a hunger strike, demanding Mr Suhr be sacked. They ended their strike last week.
The mayor, who until now had supported Mr Suhr, added: "The progress we have made has been meaningful but it hasn't been fast enough, not for me and not for Greg, and that's why I have asked Chief Suhr for his resignation."
He named Toney Chaplin as acting police chief.