LAKE ELSINORE, Calif. » A new wildfire has broken out in Riverside County near Banning, sending up a massive plume of smoke and surging toward three communities where people have been told to evacuate.

State fire officials say the fire broke out about 2 p.m. today and grew extremely quickly to 2,500 acres, or nearly 4 square miles.

TV news cameras have shown at least three structures burning. It’s not clear what they were, but they did not appear to be homes.

More than 400 firefighters are working to protecting homes.

State fire officials say mandatory evacuations have been called for the rural communities of Poppet Flats, Twin Pines and Silent Valley. It wasn’t immediately clear how many homes or people were affected.

An evacuation center has been set up at Hemet High School.