The Saddle Fire in Butte County was 50 percent contained as of Wednesday morning 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 continue working to strengthen containment lines. Steep terrain and canyon winds posed challenges for firefighters, they said.
A total of 1,626 fire personnel were on scene. Equipment included 92 fire engines, 12 bulldozers and three 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 are burning Wednesday on both sides of the west branch of the Feather River, southeast of Paradise and west of Concow. Pentz Road from Pearson to Messilla Valley roads, and Lunt Road at Highway 70 remain closed, according to Cal Fire.
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.