A brush fire burned through 25 acres and threatened structures in Riverside County's Jurupa Valley Friday amid a red flag warning due to increased wildfire risks.

The blaze was reported at 4:03 p.m. near Mission Boulevard and Crestmore Road, according to the Riverside County Fire Department, with flames moving at a moderate rate in heavy fuels.

At 5 p.m., fire officials said it was estimated to be 25 acres and 0% contained.

Earlier, the National Weather Service announced a red flag warning for much of the Inland Empire, with especially dry, windy conditions heightening the risk of wildfires breaking out and quickly spreading. Santa Ana winds swept through the region Friday.

Forecasters said valleys in San Bernardino and Riverside counties were at especially high risk, with winds forecasted to be moving at 20 to 30 miles per hour and gusts reaching up to 55 miles per hour.