Last Updated Aug 24, 2014 10:07 PM EDT
A magnitude 6.0 earthquake rocked the San Francisco Bay Area early Sunday morning, centered in the Napa County town of American Canyon, but felt across Northern California. The quake was the strongest in the region since 1989.
Gov. Jerry Brown declared a state of emergency for southern Napa County, directing state agencies to respond with equipment and personnel. President Barack Obama was briefed on the earthquake, the White House said, and federal officials were in touch with state and local emergency responders.
Napa Valley towns and communities have reported the worst damage, reports CBS San Francisco. Dozens of aftershocks in the area have been reported since the large tremor struck overnight.
There have been dozens of reported injuries, at least six of them serious, including one child who was left in critical condition by falling debris.
One hospital in the Bay Area reports it has treated at least 120 patients so far injured by the quake.
Walter Mickens, CEO for Queen of the Valley hospital in Napa, said most of those were treated for cuts, bumps and bruises. A spokesperson said earlier the facility treated a hip fracture and heart attack, but it's unclear if it was related to the tremor. The hospital has set up a triage tent as injured locals continue to come in.
The quake caused six significant fires, Napa Division Fire Chief Darren Drake said. Several other smaller fires have been reported and firefighting efforts have been complicated by broken water mains.
The temblor struck about six miles south of Napa and lasted 10 to 20 seconds, according to the United States Geological Survey.
It was the largest to shake the San Francisco Bay Area since the magnitude-6.9 Loma Prieta quake struck in 1989, collapsing part of the Bay Bridge roadway and killing more than 60 people, most when an Oakland freeway collapsed.
Dazed residents who had run out of their homes in the dark and were too fearful of aftershocks to go back to bed wandered through Napa's historic downtown, where boulder-sized chunks of rubble and broken glass littered the streets.
Dozens of homes and buildings across the Napa Valley were left unsafe to occupy, including an old county courthouse, where a 10-foot wide hole opened a view of the offices inside.
College student Eduardo Rivera said the home he shares with six relatives shook so violently that he kept getting knocked back into his bed as he tried to flee.
"When I woke up, my mom was screaming, and the sound from the earthquake was greater than my mom's screams," the 20-year-old Rivera said.
The Napa city government told Reuters there were at least 50 gas main breaks and 30 water main leaks. Officials said later there have been over 100 reports of gas leaks, although not all have been verified. Locals have told CBS San Francisco in some neighborhoods the smell of gas persists. It is also not clear yet how bad the damage from the water main breaks has been.
Power was knocked out to tens of thousands of customers in the region. Pacific Gas and Electric spokesman J.D. Guidi said close to 30,000 lost power right after the quake hit, but the number was down just under 19,000, most of them in Napa.
Napa City Councilmember Peter Mott reports the library and the historic Chinese laundry building suffered significant damage, and bricks and glass are scattered across downtown sidewalks on Second and Third Streets.
There are also reports of damage to numerous other buildings in the area. Local officials said there will be a larger police presence the next few days mostly to keep residents away from dangerous debris that has littered streets all over the area.
Napa County officials said there have so far been no reports of major infrastructure damage beyond a few roads that buckled. Some even encouraged vacationers to the popular tourist spot to not cancel their trips. Officials warned, however, that damage assessment crews were still struggling to reach and report back from many areas affected by the quake.
After the earthquake, several homes were set on fire in a mobile home park in Napa.
Resident Annalicia Salvatore told CBS News correspondent John Blackstone she felt the jolt and smelled the fumes.
"Within like 5 to10 minutes after the earthquake started, we started seeing flames come up," Salvatore said. "We looked outside and there was a bunch of flame.
Gas lines nearby had ruptured, and as homes burned firefighters found the water lines had ruptured as well.
It took twenty minutes for water pressure to be restored. By then, six homes were destroyed while nearby streets flooded.
This was the largest quake to hit the Bay Area since the 6.9 magnitude quake hit Loma Prieta in 1989. That quake occurred in the middle of a World Series game between the San Francisco Giants and the Oakland Athletics, and killed more than 60 people.
Leslie Gordon of the U.S. Geological Survey told the Associated Press the tremor struck at just before 3:30 a.m. Sunday. The epicenter was about six miles southwest of Napa, California, and about 50 miles west-southwest of Sacramento.
Jessica Turner of the U.S. Geological Survey told CBS San Francisco aftershocks of up to 5.0 are likely in the next week. There is only a 5 percent chance of a stronger quake during the next week. Already at least 25 aftershocks have rocked the region.
The USGS said the depth of the earthquake was just less than seven miles.
"A quake of that size in a populated area is of course widely felt throughout that region," Randy Baldwin, a geophysicist with the U.S. Geological Survey in Golden, Colorado, told the Associated Press. "The 6.0 is a sizeable quake for this area. It's a shallow quake."
Throughout the region, locals have reported the quake was felt as a long, rolling, shaking motion with several peaks of movement lasting for an extended time.
The California Highway Patrol reports some power outages.
The CHP is closing a bridge on Highway 37 in Vallejo while they inspect it for possible damage.
California Highway Patrol Officer Kevin Bartlett told the Associated Press there haven't been reports of injuries or people stranded in their cars, but there are numerous flat tires from motorists driving over damaged roads. Highway Patrol and the California Department of Transportation was checking roadways for damage, Bartlett said.
Widespread power outages are impacting Napa, and there are reports of minor damage across the region, mainly items falling off kitchen shelves and stores with broken bottles.
Callers to local radio stations and locals checking in on social media reported a significant shaking motion in the city of Napa, lasting for an extended time.
People as far away as the South Bay and Davis reported being woken up by the quake, which was centered 6.7 miles beneath Earth's surface.
Sonoma County also reported significant effects from the quake. The shaking was especially strong there because of the nature of the land being on alluvial gravel, sand and silt deposits, reports CBS San Francisco.
"Now that was a real earthquake," exclaimed San Francisco Sunset district resident Matt Wandell.
Several officials have said most of the damage from the quake appears confined to Napa and Sonoma counties.
The White House said President Obama, who is returning from an often-interrupted two-week vacation today, has been briefed on the earthquake. A White House spokesperson said, "federal officials are in touch with state and local responders and the President will continue to receive updates."