San Francisco police chief resigns amid racial tensions

San Francisco's police chief resigned on Thursday at the request of the city's mayor, hours after a black woman was fatally shot by an officer.

Mayor Ed Lee announced Greg Suhr's resignation at a news conference, saying he hoped to "heal the city" that has been rocked by racial tensions.

"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," Lee told a news conference.

Hours earlier, Suhr had told reporters that a 27-year-old black woman driving a stolen car was shot and killed by police after she ignored orders to stop the vehicle.

The shooting took place amid heightened tensions between San Francisco's police department and African Americans over a number of racially-charged incidents in the city.

The police department has been under intense scrutiny following the fatal shooting of Mario Woods in December and Luis Gongora in April.

It has also been embroiled in controversy over racist and homophobic text messages exchanged among officers.

"The past several months have shaken and divided our city, and tensions between law enforcement and communities of color that have simmered for too many years have come into full view," Lee told reporters at the news conference.

"These officer-involved shootings, justified or not, have forced our city to open its eyes to questions of when and how police use lethal force," he added.

The mayor said he had appointed Toney Chaplin, a 26-year veteran of the force, as acting police chief, and vowed to continue with reforms.

Activists for months had been calling for Suhr to step down and a group known as the "Frisco Five" had gone on hunger strike for nearly 17 days to press their demands.

San Francisco is just the latest California community where law enforcement is under fire for race-related issues.

Earlier this month, a senior official at the Los Angeles County sheriff's department resigned following criticism over emails he sent disparaging blacks, Muslims, Latinos and women.

Tom Angel, chief of staff to Sheriff Jim McDonnell, had forwarded the emails from his work account while serving as a top police official in Burbank city near Los Angeles in 2012 and 2013.