The Saddle Fire in Butte County was 37 percent contained as of Tuesday evening with 850 acres burned, three structures destroyed and 300 other structures threatened, the state fire control agency reported.
Fire officials said air and ground crews worked throughout the day to strengthen containment lines. Steep terrain and canyon winds posed challenges for firefighters, they said.
A total of 350 fire personnel were on scene. Equipment included 41 fire engines, 14 bulldozers and five water tenders.
The fire was first reported at 4:28 p.m. Monday near Pentz and Lime Saddle roads. The California Department of Forestry and Fire Protection, known as Cal Fire, reported that a total of five fires started on Pentz Road and rapidly grew in size.
The fires were burning Tuesday on both sides of the west branch of the Feather River, southeast of Paradise and west of Concow.
Evacuation orders remained in effect. A shelter for evacuees was opened in Chico at Neighborhood Church, 2810 Notre Dame Blvd.. A shelter for small animals was available at 2279 Del Oro Ave., Oroville, and for large animals at Camelot, 1985 Clark Road.
The cause of the fire is under investigation.