According to the San Bernardino County Fire Department, the Edgehill fire began in the Shandin Hills area and quickly spread through the neighborhood, burning residences and prompting evacuation orders, The Guardian reported.
No injuries have been reported.
The extreme heat, with temperatures reaching triple digits, has exacerbated the situation.
A total of 200 firefighters have been deployed to combat the blaze.
"Little Mountain is a community that is not unaccustomed to fire," Eric Sherwin, fire department spokesperson, said.
"The residents here are aware of fire and the threat that exists in this community. As engines were pulling up, people were already evacuating out of this area," he added.
