A firefighter during the Camarillo Springs Fire near Hidden Valley, Calif., in Ventura County on May 3, 2013.
Update 5:00 p.m. Gains grow, minor injuries reported
Cal Fire reports that firefighters now have the fire nearly 75 percent contained. Crews are now working on patrolling the fire perimeter and making sure there are no other outbreaks.
The Ventura County Star reports 8 firefighters have been treated for minor injuries.
Malibu Canyon High School remains open as a center for evacuees, Cal Fire reports.
Update 1:30 p.m.: Cost of fighting Springs Fire is $7.6 million
The Camarillo Springs fire started at "the edge of the Southbound Highway 101 approximately 1/4 mile north of the truck scales," according to a statement from Cal Fire.
Authorities say the cause of the fire "is not considered suspicious."
100 homes are still threatened but firefighters say there are no evacuation orders in place. They're hopeful the cool weather will allow them to get full containment by Monday, said Cal Fire Battalion Chief Nick Schuler.
Crews from other parts of the state are returning home.
"As fast as we were able to ramp up, it is also important to ramp down," said Schuler. "We want to be fiscally responsible."
The state has spent more than $7.6 million fighting the 28,000 acre blaze.
Update 11:20 a.m.: Cal State Channel Islands reopens to students
According to Cal State Channel Islands' website , students will be allowed back on campus Sunday evening. There will be access to student housing, the library and dining services. Classes will resume Monday morning.
The campus spokesperson, Nancy Gill, says the fire did not damage any structures on campus, but the landscape surrounding the campus is charred.
Update 10:30 a.m.: Arson ruled out
Investigators have ruled arson out of their search for what may have caused the 28,000-acre Springs Fire.
A combination of roadside grass and debris likely ignited to start the blaze, but investigators say it was unlikely that the fire was started intentionally. A statement released by CalFire says the area is vulnerable to fire:
"The area is considered a collection point for fuels and ignition sources. Do to the topography the fire quickly spread, fanned by strong east winds, referred to as 'Santa Ana's'. The fuels at the origin included dead grass, leaves, mulch, and litter where fuels are receptive to ignition and rapid spread. "
Update 9:09 a.m.: Cool weather allows crews to gain
Cool, moist air moving into Southern California is helping firefighters build containment lines around a huge wildfire burning through coastal mountains.
The Camarillo Springs wildfire continued to burn in the western end of the Santa Monica Mountains but it's 60 percent contained.
CalFire Captain Fernando Herrera said the fire has burned 28,000 acres (44 square miles) of trees and brush and damaged 15 homes.
Herrara said crews will be working the perimeter of the fire Sunday, making sure there are no unexpected flare ups. The cooler weather has given firefighters the upper hand, he said, and some personnel brought in from neighboring cities and states will return home.
The AP reports Ventura County fire officials expect full containment Monday.
Herrera said all evacuations orders have been lifted. Residents can return home.
The National Weather Service says an approaching low pressure system would bring a 20 percent chance of showers Sunday afternoon, with the likelihood increasing into the night and on Monday.
The cause of the fire is under investigation.
East of Los Angeles in Riverside County, a new fire that broke out Saturday afternoon burned 650 acres of wilderness south of Banning. It is 30 percent contained.
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