More than 425 firefighters from the U.S. Forest Service and the California Department of Forestry and Fire Protection continued to battle a brushfire in steep and virtually inaccessible terrain on Palomar Mountain on Saturday, with smoke visible in northern San Diego County and southern Riverside County.
As a precaution, the Palomar Observatory run by Caltech was closed Saturday, although the observatory was not threatened, officials said.
By nightfall, the fire was estimated at 167 acres and 20% contained. Two crews of "hotshots," experts in mountain firefighting, were inserted by helicopter, according to the U.S. Forest Service.
The Federal Aviation Administration issued a temporary flight restriction for the area to discourage anyone from flying a personal aircraft or drone above the fire.