An eight-acre brush fire propelled by strong winds destroyed at least one home in Jurupa Valley on Thursday.
Live TV news footage showed firefighters spraying water on a home consumed by flames and reduced to only its wood frame.
Riverside County sheriff's deputies evacuated 25 homes on Hudson Street between Main Street and Limonite Avenue.
A firefighter and a civilian suffered minor injuries in the fire, authorities said.
The vegetation fire was reported about 11:45 a.m. in the area of Van Buren Boulevard and 60th Street, said Jody Hagemann, spokeswoman for the California Department Forestry and Fire Protection in Riverside.
At least 75 firefighters were battling the blaze, which she said had damaged structures.
A red flag warning remains in effect until 5 p.m. Thursday as low humidity, hot temperatures and strong winds plagued the Inland Empire.
Earlier, firefighters battled a three-acre brush fire on a hillside in Whittier. That fire was 75% contained.
A third fire ignited in Chino Hills just before 1 p.m., officials said. The blaze had burned about half an acre within 30 minutes and was spreading near Butterfield Ranch Road and Pine Avenue.
Several agencies were helping to battle the blaze, including the Chino Hills Fire Department, Ontario Fire and CalFire, said Ontario Fire Department Capt. John Sitar. Firefighting aircraft were en route as of 1:30 p.m., Sitar said.