Firefighters gained ground on a brush fire near Carbon Canyon Road north of Yorba Linda, officials said.
The fire began burning in a brush covered area one mile east of Carbon Canyon Regional Park around 10:30 a.m. By afternoon, it had spread eastward towards the Los Angeles County line, charring around 100 acres, according to the Brea Fire Department.
Firefighters were able to contain about 50% of the blaze as of 2:45 p.m., the Brea Fire Department said.
Viki Peters, a nearby resident of Hollydale Mobile Home park said she's ready to leave if an evacuation is ordered.
"We've been through this before," Peters said. "If it jumps we're history. It's like a war zone already."
Three water dropping helicopters were fighting the blaze along with an airplane. The Fullerton Fire Department, Orange County Fire Authority and the Chino Valley Independent Fire District have also been called to assist.
Peters said the wind was picking up in the late afternoon and the road closures have made it difficult to get anywhere.
Carbon Canyon Road was closed between Santa Fe and San Bernadino County but the road was open from the Chino Hills side to Olinda Village.
No homes or structures are threatened yet and no injuries have been reported. No evacuations were ordered.
Residents looking for more information on the status of the fire as well as road closures can call 714-990-7732.