Rescuers searched for a person missing in a mudslide Tuesday as big yellow tractors plowed through dark, thick sludge and pushed boulders off roads after flash floods swept dirt, rocks and trees down fire-scarred slopes, washed away cars and buried buildings in small mountain communities in Southern California.

With thunderstorms forecast and more mudslides possible into Wednesday, evacuation orders remained in place in parts of the San Bernardino Mountains while a wildfire raging 500 miles (805 kilometres) to the north forced residents to abandon their homes.