The fire had burned about 1,000 acres as of 9 p.m., but retardant drops higher humidity and cooler evening temperatures slowed fire activity and 10 percent was contained by a line of cleared brush, officials said.
The fire started in an area with hard access near the Golden State (5) Freeway and Ridge Road, on the bank of Castaic Lake. Earlier in the day, another firefighter sustained a minor hand injury and was taken to a hospital.
The fire, which has been dubbed the?Lake Fire, ? is reported to be at zero percent containment as of 4:09 p.m., according to the Los Angeles County Fire Public Information Officer Twitter.
No homes were threatened, but two outbuildings were destroyed the previous day, officials said.
In northern Los Angeles County, a wildfire by Castaic Lake is burning about 0.8 of a square mile (2 square kilometers) in a remote area.
Three water-dropping helicopters and an unknown number of fixed-wing aircraft were working to help contain the blaze, Singleton said.
At 5:30 p.m. Saturday, officials were reporting "zero containment at which point, the air assault intensified".
"The wind is cooperating with us right now", Licon said shortly after 6 p.m. Saturday. "The firefighters will be out there, but there will be no shade for them".
In Riverside County over the weekend, firefighters tackled a 10-acre brush fire near Beaumont, a 40-acre fire near Moreno Valley and a 20-acre blaze just north of Lake Elsinore.
The exponential fire growth that occurred on Saturday was partly due to the tall grass that thrived in the recent rains.