Known as the Camp Fire, the blaze is burning in Butte County, in central California north of the state capital Sacramento. About 3,300 students and staff members from Paradise's 11 schools were evacuated in buses and employees' cars to a center in Chico, Butte County Schools Superintendent Tim Taylor said.
Jillian Smalley escaped her neighborhood as fire consumed everything around her. Flames and cinders crawled along the ground and up trees as she, her mother and grandmother fled the area. "I'm driving through fire as we speak".
On Thursday afternoon, California fire officials say the fire had expanded to about 18,000 acres, but its true size is hard to pinpoint because of heavy smoke, which can be seen from miles away.
At the hospital in Paradise, more than 60 patients were evacuated to other facilities and some buildings caught fire and were damaged.
California Department of Forestry and Fire Protection Capt John Gaddie told the Associated Press that some residents in Paradise had been trapped by the fire.
Hospital spokeswoman Jill Kinney said all patients were evacuated. The Butte County Sheriff's Office has issued mandatory evacuation orders for most residents of Paradise and the smaller communities of Concow and Pulga.
"We're trying to get as many people out as quickly as possible and save as many lives as we can", he said. The company also said about 14,000 residents in Butte County and neighboring Plumas County were without power. It's very surreal. Things always work out, but the unknown is a little scary.
Allana Hall captured photos of low-hanging black smoke stretching for miles as she and her boyfriend evacuated Paradise.
Shari Bernacett said she and her husband tried to get people to leave the mobile home park they manage in Paradise and had minutes to evacuate.
En route to her sister's house in Chico, she told CNN she didn't have high hopes that her home survived: "It's probably gone already".
Local media reports have shown images of traffic moving away from the plumes of smoke and orange glow of the wildfire.
Five people were burned in Paradise, according to California Highway Patrol (CHP). The warning will remain in effect until Friday morning, officials said.
Driven by strong winds and dry conditions, the blaze dubbed the Camp Fire swept through the town of Paradise, burning part of the local hospital and possibly destroying over a thousand homes and other structures, county and city officials said.
Officials issued a "red flag" warning for the area because winds had reached between 20 and 40 miles-per-hour.