A building is seen destroyed following an earthquake on August 24, 2014 in Napa, California.

The quake rocked the San Francisco Bay Area shortly after 3:00 a.m. on Sunday morning, causing damage to buildings and sending nearly 90 people to a hospital. Most injuries were non-life-threatening, but two adults and one child were critically injured, said Vanessa DeGier, spokeswoman for Queen of the Valley hospital in Napa.

Fires erupted at a mobile home park in Napa, Calif., early Sunday, August 24, 2014, following a 6.0 earthquake.

Napa Division Fire Chief Darren Drake said four mobile homes were destroyed and two others damaged by fire.

People wearing bathrobes walk down a street following a reported 6.0 earthquake early Sunday morning, August 24, 2014 in Napa, California.

Dazed residents too fearful of aftershocks wandered through Napa's historic downtown.

A house on F Street in Napa, Calif., suffered a partial roof collapse and a gas leak due to an early-morning earthquake, Aug. 24, 2014.

A Napa County firefighter sprays foam on hot spots from a fire at a mobile home park following a reported 6.0 earthquake on August 24, 2014 in Napa, Calif.

Several fires were reported, but firefighting efforts were complicated by broken water mains.

A woman walks past damage to a downtown building in Napa, Calif., August 24, 2014.

The USGS said today’s earthquake was the largest to hit the Bay Area since the 1989 Loma Prieta quake, which registered 6.9 mag. More than 60 people were killed in that disaster.

A mannequin lays amid broken glass in front of a damaged building following a reported 6.0 earthquake on August 24, 2014 in Napa, California.

A collapsed carport rests atop vehicles at Charter Oaks apartments in Napa, Calif., following an earthquake, Aug. 24, 2014. More than fifteen vehicles were trapped or crushed as multiple carports collapsed at the complex during a large earthquake early Sunday.

A building is seen destroyed following a reported 6.0 earthquake on August 24, 2014 in Napa, California.

A reporter surveys the scene of a building collapse following a reported 6.0 earthquake on August 24, 2014 in Napa, California.

Bricks from a damaged building rest on a car following a reported 6.0 earthquake on August 24, 2014 in Napa, California.

The contents of smashed bottles flows out the front doors of a business damaged by a reported 6.0 earthquake on August 24, 2014 in Napa, California.

The earthquake ripped a 10-foot chunk of bricks and concrete from the corner of the Napa County Courthouse, August 24, 2014 in Napa, California.

The facade of a building hangs over a sidewalk following a reported 6.0 earthquake on August 24, 2014 in Napa, California.

Water gushes from the ground from a water main break outside of a mobile home park following a reported 6.0 earthquake on August 24, 2014 in Napa, California.

A pedestrian walks by a mobile home that shifted off of its foundation at a mobile home park following a reported 6.0 earthquake on August 24, 2014 in Napa, California.

A man uses a garden hose to cool down hot spots from a fire at a mobile home park following a reported 6.0 earthquake on August 24, 2014 in Napa, California.

David Duncan, president and CEO of the Silver Oak Winery in Oakville, Calif., tweeted out this photo of damage from the early-morning earthquake that rattled Napa Valley Sunday, August 24, 2014.

David Duncan, president and CEO of the Silver Oak Winery in Oakville, Calif., tweeted out this photo of damage from the early-morning earthquake that rattled Napa Valley Sunday, August 24, 2014.

A cracked section of roadway is shown in the Carneros district following an earthquake, Aug. 24, 2014, in Napa, Calif. The largest earthquake to hit the San Francisco Bay Area in 25 years struck before dawn on Sunday, sending scores of people to hospitals, igniting fires, damaging historic buildings and knocking out power to thousands of homes and businesses in California's wine country.