Workers are assessing damage and have begun to clear up after a 6.0 magnitude quake in California's San Francisco Bay area, the strongest there in 25 years.
No-one has been killed but scores of people sought medical care after Sunday's quake, which struck four miles from the town of American Canyon.
The quake started fires, cracked roads, caused gas and water leaks and left dozens of buildings uninhabitable.
Governor Jerry Brown declared a state of emergency in the affected area.
President Barack Obama has also been briefed on the earthquake.'It was burning'
The city of Napa was one of the worst affected areas, with fire-fighters tackling some six blazes, as well as dozens of burst water mains and gas pipes.
Rescuers were still checking buildings overnight for anyone who might be trapped. The clear-up will gather momentum from dawn on Monday.
The Queen of the Valley Medical Center in Napa reported treating 172 people, although many were for minor injuries.
One adult is still in critical condition, while a 13-year-old boy is serious after being hit by debris from a fireplace.
Nola Rawlins, a resident of a mobile home park hit by a fire, told Associated Press: "There were some explosions, and it was burning. Everybody was out in the street. I didn't get anything out of the house."
David Gadlin, manager of an olive oil shop in Napa, told Agence France-Presse: "It could have been a lot worse if it happened when customers and workers were inside. We will get through this."
City public works director Jack LaRochelle said the major concern in Napa was the water mains system.
He said teams were working in 12-hour shifts to restore water, but that the roads were not seriously damaged and bridges were "in pretty good shape".
Electricity was initially cut off for tens of thousands but has largely been restored and the work should be completed on Monday.
Monday's school classes in Napa have been cancelled.
A museum and several historic homes were declared uninhabitable on Mare Island in Vallejo, 17 miles south of Napa.
Rails services were suspended in the San Francisco Bay area so that tracks could be checked.
The US Geological Survey (USGS) warned that aftershocks of up to 5.0 magnitude were likely in the coming week.
It said Sunday's quake struck at 03:20 local time (10:20 GMT) at a depth of 6.7 miles.
The epicentre was 51 miles from Sacramento and about 30 miles north-east of San Francisco.
California lies on the San Andreas Fault, which forms the tectonic boundary between the Pacific Plate and the North American Plate, two of the large moving plates that form the Earth's crust.
The San Francisco earthquake of 1906 and subsequent fires devastated the city.
In 1989, a powerful earthquake struck San Francisco, killing more than 60 people and injuring hundreds.
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