By CBSLA Staff

NEAR DUARTE (CBSLA) – A brush fire which sparked in the Angeles National Forest north of Duarte Sunday grew rapidly overnight, more than doubling in size by Monday morning, prompting the Los Angeles County Fire Department to issue an evacuation warning.

Sept. 6, 2020. (U.S. Forest Service)

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The Bobcat Fire has scorched 4,871 acres and still had zero containment as of 8 p.m. Monday, according to the U.S. Forest Service.

Due to the fire’s rapid growth, the Los Angeles County Sheriff’s Department directed residents in the Monrovia foothills area below the Bobcat Fire area to be prepared to evacuate. Those with large animals, horses and cattle were told to begin moving those animals.

The warning was issued to residents north of Hillcrest Boulevard and north of Greystone Avenue, along with those between Hillcrest Boulevard and Greystone Avenue, south to Foothill Boulevard.

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The blaze broke out a little after noon Sunday amid triple-digit temperatures near the Cogswell Dam and the West Fork Day Use area. California Highway Patrol officers helped campers evacuate quickly before sundown.

Structures were threatened, but its unclear if any had been damaged or destroyed. There were no mandatory evacuations. About 100 firefighters were assigned to the fire with the help of four water-dropping helicopters and five fixed-wing aircraft.

Caltrans shut down Highway 39 in both directions at El Encanto Park.

There was still no word on a cause.

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The heat wave which had engulfed the region since Friday will continue into Monday evening. A brush fire also broke out Saturday in Yucaipa, sparked by pyrotechnics. The El Dorado Fire has forced 21,000 people to flee their homes.

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#BobcatFire Update from @cityofmonrovia The Unified Incident Command Team, including the Monrovia Fire Department, United States Forest Service and the Los Angeles County Fire Department, are directing Monrovia residents in the foothill area below the Bobcat Fire to be prepared to evacuate. There continues to be rapid fire growth. Be advised– this is an Evacuation Warning which means there is potential threat to life and / or property. ⠀ ⠀ When Incident Command decides to issue an Evacuation Order, residents must leave. Please make those arrangements or plans to evacuate now in case an Evacuation Order is issued. Delaying planning arrangements may prevent fire crews from suppression activities and compromise the safety of the public and first responders. ⠀ ⠀ If an Evacuation Order is issued, the City will assist by coordinating the evacuation in two phases. ⠀ ⚠️The First Phase will be all residents residing north of Hillcrest Blvd. and north of Greystone Ave. ⠀ ⚠️The Second Phase will be all residents residing between Hillcrest Blvd. and Greystone Ave., south to Foothill Blvd. ⠀ ⠀ Residents will be notified of the evacuation order by the emergency alert system. Additionally, the Monrovia Police Department and supporting agencies will be notifying residents in the affected neighborhoods ordered to evacuate.⠀ ⠀ Beginning Tuesday morning, September 8, 2020 at 7 a.m., the City will open the Community Center as an “Information and Cooling Center” where up-to-date information can be found. The number of the Community Center is 626-256-8246. ⠀ ⠀ Residents should make evacuation plans now, including overnight accommodations. Evacuation sites for those displaced are being prepared– more information will follow should an Evacuation Order be issued. Stay informed by visiting

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