SAN FRANCISCO - An earthquake of 6.0 magnitude, the largest in the region for 25 years, shook the San Francisco Bay Area early on Sunday, waking residents and causing some power outages but no major damage, according to initial reports.
The US Geological Survey said the epicenter of the quake was eight km northwest of the town of American Canyon, on the northern edge of the Bay.
A safety dispatcher for several neighbouring cities in the area, including American Canyon and the wine-growing centre of Napa, said there were some reports of people losing power.
Police dispatchers in nearby San Francisco and Oakland said there were no reports of reports of major damage. Several people on Twitter also noted the quake but did not report damage.
Reuters reporters in Oakland felt the quake as a long, low swell that shook gently for several seconds.
The quake was the largest to hit the Bay area since the Loma Prieto quake in 1989.