ARCADIA, Calif. – A dozen aircraft dropped water and fire retardant as crews worked in steep terrain Tuesday to battle a blaze near an historic observatory and communications towers on Mount Wilson northeast of Los Angeles.
A huge plume of smoke was visible across the Los Angeles basin and surrounding valleys after the flames broke out before dawn near the 5,710-foot (1,740-meter) peak.
The 30-acre blaze was 25 percent contained by nightfall. Several hundred firefighters planned to continue the battle through the night.
The fire was on a mountainside just below the observatory and a facility that houses critical broadcast and communications antennas for the region.
"We're attacking it from the ground and the air to keep it from running uphill toward the infrastructure," said Nathan Judy, spokesman for Angeles National Forest.
Crews held the fire's growth to a few dozen acres as winds remained calm, he said.
The observatory about 25 miles northeast of downtown Los Angeles was evacuated and the fire was not burning near foothill residences.
The observatory encompasses several historic instruments including the 100-inch Hooker Telescope, one of the most famous telescopes of the first half of the 20th century. The 100th anniversary of its first observation during the night and early morning of Nov. 1-2, 1917, will be celebrated next month.