GORMAN (AP) — Campgrounds remain evacuated as crews battle a wildfire that’s burning through dry brush around an off-road recreation area north of Los Angeles.

U.S. Forest Service firefighters are getting help Sunday from LA County and Ventura County crews in fighting the fire near the Hungry Valley State Vehicular Recreation Area in an unincorporated area adjoining Los Padres National Forest. The blaze, which broke out Saturday, has burned at least 1,000 acres.

The Ventura County Star reports ground crews worked throughout the night to cut lines between the burned and untouched vegetation to help stop the fire’s spread.

The cause of the fire is under investigation.

Hungry Valley is located in the Tejon Pass along the Interstate 5 corridor, where Ventura, Kern and Los Angeles counties meet.

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