A wind-driven fire broke out Thursday in the Santa Ana River bottom in Riverside, charring three acres as crews worked to encircle the fire before it reached residential areas.
The blaze was reported at 4:50 p.m. in the area of Mission Inn Avenue and Crestmore Road, according to the Riverside Fire Department.
Multiple engine crews and truck companies from both Riverside and Riverside County converged on the location and encountered flames in thick brush, moving at a moderate rate to the east.
The fire was hundreds of yards from the nearest homes, and firefighters were attempting to get ahead of the blaze to prevent it from entering neighborhoods, according to reports from the scene.
No Cal Fire aircraft were immediately called to the location.
The river bottom is dotted with dozens of homeless encampments, but it was not immediately known whether the blaze was human-caused.