"Firefighters made good progress throughout the night on the Bonny Fire, however extremely rugged and steep terrain remains a challenge," the Riverside County Fire Department reported Sunday morning. "The change in weather patterns and continued chance of thunderstorms today and tomorrow heightens risk of erratic fire behavior. Today, firefighters will continue cooling hot spots and constructing containment line around the fire perimeter."
The Bonny Fire was reported at 2:50 p.m. Thursday near Bonny and Barber lanes, according to the fire department. Full containment isn't expected until Aug. 7.
One firefighter was injured battling the blaze, but fire officials offered no further details.
The force battling the flames included 1,884 firefighters from Riverside and cooperating agencies, officials said. Five helicopters and numerous air tankers were working overhead.
The fire threatened 786 structures and destroyed one outbuilding.
An evacuation order remained in effect for the area north of the San Diego County line, east of Bonny Lane, south of Bowers Road, Bailey Road and Ramsey Road and west of Anza Borrego State Park.
An evacuation warning was also issued at noon Saturday to include the area of south of La Cima Road/Indian Paint Brush Road, west of Anza Borrego State Park, north of the San Diego County line and east of Spanish Spur Trail, according to the Riverside County Fire Department.
A care and reception center was established at Hamilton High School in Anza. The county Department of Animal Services stationed personnel at the location to assist with displaced animals, who were being housed at the San Jacinto Animal Campus at 581 South Grand Ave.
Shortly after it started Thursday, the fire nearly swept across Chapman and Johnston roads, prompting Cal Fire air tankers and water-dropping helicopters to unload in the immediate vicinity of several homes, protecting them from damage, according to reports from the scene.
On Thursday evening, the head of the fire jumped a road amid light winds and moved into hills, creating challenges for ground personnel. The fire prompted the South Coast Air Quality Management District to issue a smoke advisory.
The cause of the fire was under investigation.