BAY AREA, CA — A magnitude 5.6 earthquake struck Northern California on Wednesday morning, rattling homes, knocking out power to thousands of residents, damaging property across the North Bay, and sending more than a million earthquake warnings to cellphones as officials worked to assess the extent of injuries and damage.
The earthquake struck at 8:10 a.m. at a depth of about 5 miles, according to the U.S. Geological Survey.
The epicenter was in a rural stretch of Mendocino County dotted with small agricultural communities about an hour from wine country and 140 miles northeast of San Francisco.
A magnitude 2.5 aftershock followed shortly afterward, and three additional quakes measuring less than magnitude 2.7 struck near the epicenter within an hour.
Residents across Sonoma County, Lake County, Napa County, Marin County, and throughout the Bay Area reported shaking. Some residents said they felt the earthquake as far away as Lake Tahoe.
County officials continued damage assessments Wednesday as reports surfaced of shattered windows, fallen objects, damaged businesses, and widespread power outages.
Pacific Gas and Electric reported that 4,378 customers in Willits and Redwood Valley lost power immediately after the earthquake.
Additional outages occurred farther north, while Mendocino County officials later reported that more than 6,000 residents in six communities near the epicenter were affected, according to the AP.
Officials urged residents to stay off highways and local roads while crews inspected infrastructure and made repairs.
Across the North Bay, residents described swaying light fixtures, rattling dishes, shaking windows, and rolling motion as the quake moved through the region.
In Upper Lake and Kelseyville, residents reported items falling from shelves and shattered glass, though no immediate injuries were reported.
In Kelseyville, resident Alan Harris said he received an earthquake alert on his cellphone moments before the shaking began.
"I yelled downstairs immediately to my wife and daughter to make sure they were hanging on," Harris told the Associated Press. "It was scary. You could hear things crashing, mostly on the third floor of the house."
Security camera footage inside Harris' home captured vigorous shaking and the sounds of objects crashing before he called out, "Is everyone OK?" according to the AP.
The shaking lasted about 30 seconds, Harris said. Framed photos fell from walls, and a computer monitor tipped over, but he found no major structural damage.
Even in Healdsburg, about an hour south of the epicenter along Highway 101, residents described a sudden back-and-forth motion that jolted homes and awakened sleeping residents.
"The alert is shocking woke me up so quickly and frightened that I think the adrenaline in my body overrode any feeling of shaking and nothing in my room on the shelves appeared to move," a Healdsburg woman wrote on Facebook.
In Clearlake, one resident compared the shaking to the 1989 Loma Prieta earthquake. "Came in two waves here in Kelseyville. Pool water splashed out in waves and lots of creaking & shaking," another resident wrote online.
The earthquake was the strongest to strike the area around Mendocino County since 1940, according to veteran California seismologist Lucy Jones, who spoke with the AP.
"The area is not without earthquakes, but they're usually smaller than this," Jones said, adding that aftershocks were likely but would "probably stay on the low side."
At Club Calpella Restaurant, about 10 miles south of the epicenter, employee Brie Leon said the building shook so hard that bottles and frames crashed to the floor.
"I had just turned the open sign on and went back into the kitchen, and that's when it happened," Leon told the AP. "It almost felt like something hit the building."
Leon said the quake knocked picture frames off walls and bottles from shelves in both the restaurant and an adjoining stockroom.
"It wasn't a big, big quake, but things went everywhere," she told the AP.
Hospitals also reported some injuries following the quake, although officials had not yet released details about their number or severity, Mendocino County spokesperson Heather Rose told the AP.
Nearly 657,000 earthquake early-warning alerts were delivered through California's MyShake app alone, according to the California Governor's Office of Emergency Services. State officials said they had not received reports of major damage or serious injuries but were coordinating with local authorities to evaluate impacts.
That included residents in Napa and Marin counties, who received earthquake warnings, although many reported only light shaking.
Hundreds of thousands of additional alerts were delivered through other warning systems, pushing the total number of notifications well beyond one million, ShakeAlert operations scientist Robert de Groot said.
"The alert deliveries for this are going to be well over a million."
The Associated Press contributed to this report.
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