The northern California town, called Paradise, is about 150 km north of Sacramento, the state capital, reports Xinhua news agency.
"The whole town's on fire," Scott Lotter, a town councilman who evacuated with his family, told the media on Thursday, adding, "It's pretty grim."
Video posted online showed that the blaze devoured trees and houses along the highway.
A thick, dark plume of smoke filled the sky in the video.
Fueled by steady winds and dry grass, the blaze, dubbed Camp Fire, was first reported at about 6.30 a.m. on Thursday and it rapidly exploded to an estimated 18,000 acres by 2.30 p.m.
Cal Fire said the fire had zero containment so far.
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
