The fire captain in the city of napa, California, says it was the worst shaking he has ever experienced. The quake hit in the dead of night setting off raging fires like this one sending bottles... See More
The fire captain in the city of napa, California, says it was the worst shaking he has ever experienced. The quake hit in the dead of night setting off raging fires like this one sending bottles flying off the shelves in the heart of wine country and damaging historic buildings in downtown napa, which is a Mecca for tourists. In fact, you could see some of them wandering through the streets in their bathrobes after being jolted so rudely out of bed. And look at this surveillance video. Cameras rolling during the quake itself. Vehicles shaking as debris falls all around, and there it is on the map, the magnitude 6.0 quake hitting just north of San Francisco. The governor has declared a state of emergency tonight, and we have team coverage of the napa valley earthquake starting with ABC's Ryan Owens right there in napa tonight. Ryan, good evening. Reporter: Good evening to you, Dan. Apocalyptic, that may be the best word to describe the scene behind me. Would you look at these mobile homes or what's left of them. They were incinerated when all of that shaking snapped some gas lines and this is just some of the damage done by that quake in the middle of the night. Earthquake. It's an earthquake. Reporter: 3:20 A.M., a powerful quake jolts tens of thousands right out of bed. The 6.0 is the strongest to hit northern California in more than two decades. This family just trying to make sure everyone is okay. Dozens of buildings in napa's historic downtown are damaged. An entire wall of this second story building gone. And roads ripped apart and buckled. The quake also ruptured gas lines causing these mobile homes to explode in flames. Four of them destroyed. Another two with major damage. I felt the earthquake, and I looked out of my front window immediately, and I saw flames. Fire just exploded just in a matter of a couple minutes. It just erupted. It was frightening. It was terrifying. Reporter: The earthquake also broke water mains which made fighting the fires futile. With no water to douse them, firefighters could do little more than watch the homes burn. We did have a major water main break just outside the mobile home park and we -- which really complicated the fire fight. It did make things more difficult for us. Reporter: The firefighters were able to stop the flames from spreading, but for these residents, it was just too late. The Earth moved. The house moved. We didn't really know what happened. The house was already on fire, and it was hard to get out. It was really scary. I feel like we lost everything. Yeah, we lost everything. But we're -- not everything. Not everything, honey. Reporter: But at least they weren't hurt. 120 people here are. Doctors say most have cuts and bruises, but three patients have critical injuries including a child hit by a piece of a crumbling chimney. Approximately 20,000 people here still do not have power tonight. That number has been improving throughout the day, but restoring water, that is a different story, Dan. Some of these residents have been told by city officials they may be without water here for up to a week. Not a pleasant thing to hear. We are thinking about that child, of course, tonight, the child injured. Ryan, thank you.
This transcript has been automatically generated and may not be 100% accurate.