More than 150 people were injured and hundreds of homes destroyed when a magnitude 6.0 earthquake hit near Napa Valley, in northern California Sunday.
It was the strongest earthquake to strike the region since the 6.9 Loma Prieta quake in 1989.
"There was some explosions, and it was burning and everybody was out on the street," Nola Rawlins, who lost her home in the fire, said.
The tremors were so strong they burst gas lines in a mobile home community.
"We did have a major water main break just outside the mobile home park, which really complicated the fire fight," Darren Drake, with the Napa City Fire Department said.
In the historic downtown area, bricks crumbled from buildings, windows shattered, and streets buckled.
At one point at least 64,000 residents were without power.
Operation Blessing arrived on the scene Monday to help residents with clean-up.
"Operation Blessing is going to be working with local churches and local emergency management to help the residents of California get back on their feet," Dan Moore, U.S. Disaster Relief Director with Operation Blessing, said.
California is on the geological Ring of Fire, putting it at great risk for major quakes.
As clean up begins, scientists continue to warn that California is in the danger zone for a much bigger one.
Scientists estimate there's a 99 percent chance of a quake 6.7 magnitude or larger in the next 30 years, especially in Southern California.
"The question is not if but when Southern California will be hit by a major earthquake - one so damaging that it will permanently change lives and livelihoods in the region," A 2008 study by the U.S. Geological Survey said.