(Updates homes burned, adds evacuee quotes, details)
By Steve Gorman
LOS ANGELES, Nov 15 (Reuters) - A wildfire whipped up by hurricane-force gusts raged through northwestern Los Angeles foothills on Saturday, burning some 165 homes and threatening the power supply of California's largest city.
More than 10,000 residents were under mandatory evacuation orders as the fire, which has burned more than 2,600 acres, spread westward fanned by dry winds.
A separate fire burned a second day in the celebrity enclave of Montecito, where 111 homes have been destroyed.
Los Angeles Mayor Antonio Villaraigosa said the fire in the foothills at the edge of San Fernando Valley near Sylmar had destroyed more than any other in the past decade and that flames could take down power lines.
"The fire is threatening the power of the city of Los Angeles," Villaraigosa told a news conference. "We may have to move to rolling blackouts."
He urged residents to evacuate if they were in harm's way.
"If you wait until the fire gets there you have waited too long," Villaraigosa said. "This fire can be on you in a moment's notice."
He also asked Los Angeles residents to conserve power.
Governor Arnold Schwarzenegger declared a state of emergency in Los Angeles County, opening the way to additional resources.
Police closed down Interstate 5, the main freeway linking Los Angeles to the north, and other roads as 600 firefighters mobilized. Transmission lines bringing power follow the Interstate highway 5 corridor through the mountains north of Los Angeles, home to nearly 10 million.
Mountains were engulfed in flames and billows of smoke visible from space by weather satellite. Steady gale-force winds, blowing at 35 mph (56 kph), periodically gusted up to 75 mph (120 kph) and spread the fire. A map of the fire is at tinyurl.com/sayrefire.
Residents of a destroyed mobile home park sat in the gymnasium of the Sylmar High School, where the American Red Cross had set up relief services.
"You could see absolutely nothing," said Jackie Burns, 77, who, along with her husband, Len, fled their mobile home at 3 a.m. as the fire raged through the neighborhood. "It was like looking into a black hole. It looked like the end of the world to me."
DRY CONDITIONS 'PERFECT FOR MORE' Continued...
The recent wildfires in Los Angeles, California, have burned more than 42,000 acres (17,000 hectares) of land. Nearly 1,000 homes were destroyed, and more than 10,000 residents were evacuated. 

Los Angeles Mayor Antonio Villaraigosa expressed concerns that Los Angeles was on the verge of a blackout, and California Governor Arnold Schwarzenegger has declared the situation a state of emergency. In terms of property damage, this fire is the worst since the Bel Air fire in 1961. Los Angeles County Supervisor Zev Yaroslavsky stated, "Whether you live in a mobile home park or you live in an estate, when you lose your home it's devastating."
Saturday: the Sayre Fire burns in the background 
In Montecito, a census-designated place in Santa Barbara County, the homes of many celebrities, including Steven Spielberg, Steve Martin, Eric Schmidt, and Rob Lowe, have been destroyed. This massive fire has caused millions of dollars of damage and 13 injuries. Rob Lowe declared that "it was just like Armageddon."

According to one official, the fire started when ten students lit a bonfire on a ridge but failed to extinguish it. Although Santa Barbara County Sheriff Bill Brown believes that "this fire was the result of carelessness, not criminal intent," the county district attorney will still have to review the case.
The Montecito Tea Fire on November 13 
Santa Ana winds with gusts up to 70 mph exacerbated the Montecito fire, which destroyed over 100 buildings and damaged many others, including Westmont College. The college's 1000 students were forced to take shelter in the gymnasium.

A spokesman for the college, Scott Craig, described the scene: "I saw flames about 100 feet high in the air shooting up with the wind just howling. Now when the wind howls and you've got palm trees and eucalyptus trees that are literally exploding with their hot oil, you've got these big, red hot embers that are flying through the sky and are catching anything on fire."

Officials now report that firefighters are making some progress. Of the three major fires, the Montecito Tea Fire is 95% contained; the Sayre Fire, 70%; and the Triangle Complex Fire, 75%. Officials have lifted the evacuation order for Chino Hills as well.