State fire officials have brought in hundreds of additional firefighters to battle a Central California blaze that is threatening about 100 rural homes.

The fire burning in foothills near Lake McClure in Mariposa County nearly doubled in size overnight to 900 acres and was 10 percent contained. The threatened homes are under evacuation orders. State fire spokesman Daniel Berlant says about 500 firefighters were battling the Hunters Fire on Tuesday morning, up from 100 firefighters when the blaze began a day earlier.

Berlant says steep terrain and dry brush are making it difficult for crews to get a handle on the blaze. Temperatures are also high and are expected to be in the 90s on Tuesday.

Berlant says the conditions are similar to what firefighters would encounter during the summer.